The Estate of Orville Bruce appeals the circuit court’s judgment for the State in its claim against the estate for reimbursement of Medicaid payments made to Orville Bruce’s deceased wife, Minnie. The State asserted a right to the reimbursement pursuant to Section 473.399, RSMo 2000. The estate responded that federal law, 42 U.S.C. Section 1396p, preempts reimbursement under Section 473.399. We agree and reverse the circuit court’s judgment for the State.
Minnie Bruce received Medicaid benefits from October 1990 until she died on February 28, 2002. No probate estate was administered for her. On April 17, 2005, Orville Bruce died. He never received Medicaid benefits. His estate consisted of a house and an automobile. Bruce had owned the house jointly with his wife as tenants by the entirety. His estate was liquidated to $97,000. Pursuant to Section 473.399, the State sought $150,528.63 from the estate for reimbursement of the Medicaid payments to Minnie Bruce. The circuit court granted the State’s claim.
In its only point on appeal, Bruce’s estate asserts that the circuit court erred because, although Section 473.399 permits the State to seek reimbursement from a spouse’s estate, the United States Congress enacted Section 1396p that forbids such a claim. The estate argues that the federal statute preempts enforcement of Section 473.399 pursuant to the United States Constitution’s supremacy clause.1 This clause says that federal law “shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.” U.S. Const, art. VI, cl. 2. Federal law preempts state law in three situations: (1) express preemption, when a federal directive expressly declares that the federal law preempts state law, (2) implied field preemption, when “the scheme of federal regulation is so pervasive as to make reasonable the inference that Congress left no room for the States to supplement it,” and (3) conflict preemption, when “compliance with both federal and state regulations is a physical impossibility, or where state law stands as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress.” Jensen v. Missouri Department of Health and Senior Services, 186 S.W.3d 857, 860 (Mo.App. 2006).
Medicaid is a cooperative federal — state program designed to assist the states in providing health care to people *401who cannot afford it. McNeil—Terry v. Roling, 142 S.W.3d 828, 833 (Mo.App. 2004). If a state opts to participate in the program, it must comply with all federal statutory and regulatory requirements. Id. Because Medicaid is a cooperative program, it is not susceptible to express or implied field preemption. It is susceptible only to conflict preemption. Jensen, 186 S.W.3d at 860-61.
Missouri has opted to participate in the Medicaid program. Gee v. Department of Social Services, Family Support Division, 189 S.W.3d 621, 623 (Mo.App.2006). In Section 473.398 and 473.399, RSMo 2000, the General Assembly authorized Missouri’s Medicaid authorities to obtain reimbursement from a recipient’s estate after the recipient’s death or from the estate of the recipient’s spouse after the spouse’s death. Section 473.399.2 says:
For the purposes of this section, the providing of assistance shall create an obligation which may be recovered by filing a claim in the probate division of the circuit court against the decedent estate of the spouse of the deceased recipient upon such spouse’s death as provided by the probate code of Missouri, chapters 472, 473, 474 and 475, RSMo. The amount of the state debt shall be the full amount of assistance without interest provided to the recipient during the marriage of such recipient and spouse; provided that the liability of the obligor estate shall not exceed the value of the combined resources of the recipient and the spouse of the recipient on the date of death of the recipient.
Orville Bruce’s estate asserts that Section 473.399, which clearly authorizes spousal recovery, conflicts with 42 U.S.C. Section 1396p, which clearly prohibits it in this case.
When interpreting a statute, the judiciary’s primary task is to ascertain legislative intent. The preferred means for doing this is to accord the statute’s language its plain and ordinary meaning. Cline v. Teasdale, 142 S.W.3d 215, 222 (Mo.App.2004).
Section 1396p(b) says:
Adjustment or recovery of medical assistance correctly paid under a State plan
(1) No adjustment or recovery of any medical assistance correctly paid on behalf of an individual under the State plan may be made, except that the State shall seek adjustment or recovery of any medical assistance correctly paid on behalf of an individual under the State plan
A. In the case of an individual described in subsection (a)(1)(B) of this section, the State shall seek adjustment or recovery from the individual’s estate or upon sale of the property subject to a lien imposed on account of medical assistance paid on behalf of the individual.
B. In the case of an individual who was 55 years of age or older when the individual received such medical assistance, the State shall seek adjustment or recovery from the individual’s estate, but only for medical assistance consisting of — (i) nursing facility services, home and community — based services, and related hospital and prescription drug services, or (ii) at the option of the State, any items or services under the State plan.
C. (i) In the case of an individual who has received (or is entitled to receive) benefits under a long — term care insurance policy in connection with which assets or resources are disregarded in the manner described in clause (ii), except as provided in such clause, the State shall seek ad*402justment or recovery from the individual’s estate on account of medical assistance paid on behalf of the individual for nursing facility and other long — term care services[.]2
In Section 1396p(b), the United States Congress plainly restricts recovery of Medicaid benefits from a recipient’s estate to three specific situations, and none authorizes a state to seek recovery from the recipient’s spouse. Because Congress has mentioned these three situations expressly, we infer that it intended to exclude recovery in other situations. Groh v. Ballard, 965 S.W.2d 872, 874 (Mo.App.1998). See also In re the Estate of Budney, 197 Wis.2d 948, 541 N.W.2d 245, 246 (App. 1995) (“[Section 1396p(b) ] does not counter the initial blanket prohibition by specifically authorizing a State to recover medical assistance benefits paid on behalf of a recipient from a surviving spouse’s estate[.]”); Hines v. Department of Public Aid, 221 Ill.2d 222, 302 Ill.Dec. 711, 850 N.E.2d 148, 153 (2006) (“No provision [in Section 1396p(b)] is made for collection from the estate of the recipient’s spouse.”).
Although Section 1396p(b) authorizes recovery only from the recipient’s estate, it allows states to define “estate” in such a way that will permit recovery from traditionally non-probate property. Concerning this issue, Section 1396p(b)(4) says:
For purposes of this subsection, the term “estate,” with respect to a deceased individual—
A. shall include all real and personal property and other assets included within the individual’s estate, as defined for purposes of State probate law; and
B. may include, at the option of the State (and shall include, in the case of an individual to whom paragraph (l)(C)(i) applies), any other real and personal property and other assets in which the individual had any legal title or interest at the time of death (to the extent of such interest), including such assets conveyed to a survivor, heir, or assign of the deceased individual through joint tenancy, tenancy in common, survivor-ship, life estate, living trust, or other arrangement.
Applying the plain and ordinary meaning of Section 1396p(b)(4)A’s language, we conclude that an estate, for the purpose of Medicaid recovery, must include all of what Missouri’s probate law would define as a recipient’s estate. We understand “shall” as a mandate. SSM Health Care St. Louis v. Schneider, 229 S.W.3d 279, 281 (Mo.App.2007). Section 1369p(b)(4)B, on the other hand, by using “may,” grants Missouri permission to include any of the recipient’s other property and assets that would traditionally fall outside the recipient’s probate estate. Estate of Parker, 25 S.W.3d 611, 616 (Mo.App.2000) (“ ‘[M]ay’ in a statute implies alternate possibilities and that the conferee of the power has discretion in the exercise of the power.”).
Section 1396p(b)(4)B empowers Missouri to define “estate” broadly and thereby to pursue property that a recipient owned jointly with another individual when the recipient died but that would not be included in the decedent’s estate. If a surviving spouse’s estate includes property that was owned jointly with a deceased Medicaid recipient, Section 1396p(b) permits a state to trace this property back to the recipient and to recover it as a reimbursement. In the Estate of Shuh, 248 S.W.3d 82, 85-86 (Mo.App.2008); Hines, 302 Ill.Dec. 711, 850 N.E.2d at 154; Estate of DeMartino v. Division of Medical Assistance and Health Services, 373 N.J.Super. 210, 861 A.2d 138, 145 (2004); State Department of *403Human Resources Welfare Division v. Estate of Ullmer, 120 Nev. 108, 87 P.3d 1045, 1050 (2004); Janel C. Frank, Note, How Far is Too Far? Tracing Assets in Medicaid State Recovery, 79 N.D.L.Rev. 111, 130-31 (2003). Hence, although Section 1396p(b) does not permit recovery from a spouse’s estate, Missouri’s Medicaid program could still recover from the estate of a recipient’s spouse if Missouri’s probate law defined a Medicaid estate to include property not susceptible to probate, including property owned by tenants by the entirety.
For the purposes of probate, the General Assembly has defined “estate” as “the real and personal property of the decedent or ward, as from time to time changed in form by sale, reinvestment or otherwise, and augmented by any accretions and additions thereto and substitutions therefor, and diminished by any decreases and distributions therefrom[J” Section 472.010(11), RSMo 2000. Although this definition is vague, case law has held consistently that probate law does not govern the passing of property owned by tenants by the entirety. See Rinehart v. Anderson, 985 S.W.2d 363, 367 (Mo.App. 1998) (property passes immediately to surviving spouse and is not subject to probate); In re Estate of Hughes, 735 S.W.2d 787, 791 (Mo.App.1987).
Probate’s non — application to tenancy by the entirety results from its being a form of ownership that is created by marriage in which each spouse owns the entire property, rather than a share or divisible part. Rinehart, 985 S.W.2d at 367. It is based on a legal fiction that the husband and wife own the property jointly as a single person. In re Estate of Hughes, 735 S.W.2d at 791. Together, each has an undivided interest. Id. When one of the spouses dies, the surviving spouse becomes the property’s sole owner by virtue of being owner of 100 percent of the property. Id. Hence, property owned by Minnie and Orville Bruce as tenants by the entirety was not part of Minnie Bruce’s probate estate and did not fit within the definition of “estate” enunciated in Section 472.010(11). Rinehart, 985 S.W.2d at 367; In the Matter of Estate of Hughes, 735 S.W.2d at 791. The State, therefore, could not use Section 1396p(b)(4)A to seek recovery from Bruce’s estate.
Nor could the State recover from Orville Bruce’s estate because the General Assembly has not taken the step required by Section 1396p(b)(4)B to adopt a definition of estate for the purpose of Medicaid recovery to include such property. For example, the New Jersey legislature, unlike Missouri, has adopted a definition of estate that includes:
[A]ll real and personal property and other assets included in the recipient’s estate as defined in N.J.S. 3B:1-1, as well as any other real and personal property and other assets in which the recipient had any legal title or interest at the time of death, to the extent of that interest, including assets conveyed to a survivor, heir or assign of the recipient through joint tenancy, tenancy in common, sur-vivorship, life estate, living trust or other arrangement.
N.J.Rev.Stat. Section 30:4D-7.2a(3) (1995).3 Until the General Assembly takes *404this step, Missouri’s Medicaid program will not be able to recover property possessed by a successor by virtue of being owned as a tenant by the entirety.
The State argues that Section 461.300, RSMo 2000, expands the definition of estate to include property held as tenants by the entirety. Section 461.300.1 says:
Each recipient of a recoverable transfer of a decedent’s property shall be liable to account for a pro rata share of the value of all such property received, to the extent necessary to discharge the statutory allowances to the decedent’s surviving spouse and dependent children, and claims remaining unpaid after application of the decedent’s estate[.]
Section 461.300 authorizes the court to expand the decedent’s estate when the estate is insufficient to pay its creditors. Even assuming that the State is a creditor that could make a claim under Section 461.300, the State’s contention fails because the house that Minnie Bruce and her husband owned as tenants by the entirety was not a recoverable transfer under the statute. Section 461.300.10(4) defines a recoverable transfer:
[A] nonprobate transfer of a decedent’s property under sections 461.003 to 461.081 and any other transfer of a decedent’s property other than from the administration of the decedent’s probate estate that was subject to satisfaction of the decedent’s debts immediately prior to the decedent’s death, but only to the extent of the decedent’s contribution to the value of such property.
To meet this definition, Bruce’s house would either have to be a “nonprobate transfer of decedent’s property” or “property ... that was subject to satisfaction of the decedent’s debts immediately prior to the decedent’s death.” Property held by tenants by the entirety does not fit within either of these categories.
Section 461.005(7), RSMo 2000, defines a non — probate transfer as “a transfer of property taking effect upon the death of the owner, pursuant to a beneficiary designation,” and it does not include “survivor-ship rights in property held as joint tenants or tenants by the entirety[.]” And property held by tenants by the entirety is not subject to satisfaction of the decedent’s debts. In Missouri, creditors are not able to levy on this property to satisfy the debts or claims of one spouse. Farmers Exchange Bank v. Metro Contracting Services, Inc., 107 S.W.3d 381, 395 (Mo.App. 2003).
Hence, Orville Bruce’s house was not a recoverable transfer under Section 461.300. Even assuming that the General Assembly intended for Section 461.300 to expand the definition of the estate for Medicaid recovery purposes, it did not expand it to cover property held by tenants by the entirety.
Equally flawed is the dissent’s suggestion that the General Assembly used Section 473.399.2 to expand the definition of a Medicaid estate. As we noted above, Section 473.399.2 says:
For the purposes of this section, the providing of assistance shall create an obligation which may be recovered by *405filing a claim in the probate division of the circuit court against the decedent estate of the spouse of the deceased recipient upon such spouse’s death as provided by the probate code of Missouri, chapters 472, 473, 474 and 475, RSMo. The amount of the state debt shall be the full amount of assistance without interest provided to the recipient during the marriage of such recipient and spouse; provided that the liability of the obligor estate shall not exceed the value of the combined resources of the recipient and the spouse of the recipient on the date of death of the recipient.4
If, as has been suggested, the General Assembly intended for this statute to expand the definition of an individual Medicaid recipient’s estate to include non — probate property, it could not have chosen a more oblique and crabbed manner for doing so. Indeed, many of the states whose courts have declared that the law permits spousal recovery did so only because those states’ legislatures had adopted definitions that closely track the language of Section 1396p(b)(4)B. See In re Estate of Laughead, 696 N.W.2d 312, 315 (Iowa 2005); Estate of DeMartino, 861 A.2d at 143; Ullmer, 87 P.3d at 1050.5
We are dubious that Missouri would have elected to shroud its expansion of the definition of a Medicaid estate in discussions of the limits on the value of the property to be recouped. Such a prospect is highly unlikely. Indeed, the Supreme Court has instructed that the primary rule of statutory construction is to glean legislative intent by understanding the statute according to its objective. Nixon v. Quik-Trip Corporation, 133 S.W.3d 33, 37 (Mo. banc 2004). The objective that the General Assembly articulated in Section 473.399 was to authorize spousal recovery and to set a limit on how much could be recouped from the obligor’s estate. Nothing in the statute’s language indicates that its objective was to expand the definition of a Medicaid estate. Even had the General Assembly decided to take an oblique and crabbed route to redefining a Medicaid estate, surely it would have declared that the liability of the obligor’s estate extended only to the spouses’ combined resources instead of saying that the “liability of the obligor estate shall not exceed the value of the combined resources of the recipient and the spouse.”6 The General Assembly’ use of this phrase establishes that the Section 473.399’s second sentence was the monetary limit for spousal recovery.
Although the General Assembly enacted Section 473.399.2 for the obvious purpose of facilitating spousal recovery, it did so in 1990. Laws of Missoum 1990. At that time, however, federal law did not give the states the option of defining estate to include non — probate property. Federal authorization for recoupment of non — probate property — provided a state redefined a Medicaid estate to allow it — did not come until three years after the General Assembly enacted Section 473.399.2. See FRANK, 79 N.D.L.Rev. at 118 (Congress amended Section 1396p during 1993 to include the definition of estate currently found in Section 1396p(b)(4)).
That Section 473.399.2 predated federal authorization is quite telling in eliminating the possibility that the General Assembly intended for the statute to expand the definition of a Medicaid estate. Obviously, *406the General Assembly did not enact Section 473.399.2 because it foresaw Congress’s enactment of Section 1394p(b)(4). The timing of Section 473.399’s enactment belies a notion that its purpose was to expand the definition of a Medicaid estate.
The State avers numerous public policy reasons as to why we should interpret Section 1396p(b) as providing for spousal recovery. While these public policy reasons may be valid, we are constrained by the language of Section 1396p(b). It simply does not permit spousal recovery under Missouri’s present statutes. Missouri has not opted, as other states have, to take advantage of the authority afforded by Section 1396p(b)(4)B to define a Medicaid estate in such a manner as to capture traditionally non — probate assets. If the General Assembly wanted to empower Missouri’s Medicaid program to recover non — probate assets, all it need do is redefine “estate” for purposes of Medicaid recovery, but it has not done so.
For these reasons, we reverse the judgment of the circuit court. We remand the case to it so it can vacate its judgment for the State and enter judgment for Orville Bruce’s estate.
JAMES M. SMART, JR., Judge, concurs. JOSEPH M. ELLIS, Judge, dissents in a separate opinion.. Although the parties did not raise an issue concerning jurisdiction, we have a duty sua sponte to address issues of our jurisdiction. State v. Miller, 172 S.W.3d 838, 843 (Mo.App. 2005). Article V, Section 3, of Missouri’s constitution, grants the Supreme Court “exclusive appellate jurisdiction in all cases involving the validity of a treaty or statute of the United States, or of a statute or provision of the constitution of this state[.]” This provision gives the Supreme Court exclusive jurisdiction over the constitutional validity of a state statute. Miller, 172 S.W.3d at 843. Hence, if the issue of preemption created a question concerning the statute’s validity, we would not have jurisdiction to address the issue. Preemption, however, does not concern the statute’s validity. It merely presents an issue of whether or not a statute must yield to the dictates of a federal directive by virtue of the United States Constitution’s supremacy clause. Because, in reviewing a preemption challenge, we do not determine whether or not a state statute is unconstitutional, we have jurisdiction to review Bruce’s claim. This position is consistent with numerous appellate court decisions that have decided preemption cases. See e.g., Jensen v. Mo. Dep’t of Health & Senior Servs., 186 S.W.3d 857 (Mo. App.2006); City of Belton v. Smoky Hill Ry. & Historical Soc’y, Inc., 170 S.W.3d 429 (Mo. App.2005).
. We added the emphasis.
. Other examples of states that have taken this course are Iowa and Nevada. The Iowa legislature has defined a Medicaid estate to include “any real property, personal property, or other asset in which the recipient, spouse, or child had any legal title or interest at the time of the recipient’s, spouse's, or child’s death, to the extent of such interests, including but not limited to interests in jointly held property, retained life estates, and interests in trusts.” Iowa Code Ann. Section 249A.5(2)(c) (2003). Similarly, Nevada has defined a Med*404icaid estate as "all real and personal property and other assets included in the estate of a deceased recipient of Medicaid and any other real and personal property and other assets in or to which he had an interest or legal title immediately before or at the time of his death, to the extent of that interest or title. The term includes, without limitation, assets conveyed to a. survivor, heir or assign of the deceased recipient through or as the result of any joint tenancy, tenancy in common, surviv-orship, life estate, living trust, annuity, declaration of homestead or other arrangement.” Nev.Rev.Stat. Section 422.054 (2003).
. We added the emphasis.
. Iowa’s expansive definition of Medicaid estate appears supra, at 403. New Jersey’s and Nevada’s expansive definitions of Medicaid estate appear supra, at Note 3.
.We added the emphasis.