{¶ 1} R.C. 3111.13(F)(3)(a), as amended effective October 27, 2000, provides that when a court issues an order requiring a parent to pay current child support, the court shall not require that parent to pay any amount for failure to pay such support before the order if “(i) [a]t the time of the initial filing of an action to determine the existence of the parent and child relationship with respect to that parent, the child was over three years of age,” and “(ii) [pjrior to the initial filing of an action to determine the existence of the parent and child relationship with respect to that parent, the alleged father had no knowledge and had no reason to have knowledge of his alleged paternity of the child.”
{¶ 2} We are asked to determine whether R.C. 3111.13(F)(3)(a) violates Section 28, Article II of the Ohio Constitution, which prohibits the General Assembly from passing retroactive laws, when applied to a judgment ordering payment of a child-support arrearage that existed prior to the statute’s amendment. We hold that R.C. 3111.13(F)(3)(a) as applied to this case is unconstitutionally retroactive.
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{¶ 3} In December 1986, appellant, Matthew Smith, and appellee, Shirley Smith, engaged in a romantic relationship. Shortly after their relationship ended in early 1987, Shirley learned that she was pregnant, and subsequently gave birth on October 27, 1987. Though Shirley believed Matthew to be the father of her child, she did not notify him of the child’s existence until the Hancock County Department of Human Services commenced paternity proceedings on Shirley’s behalf almost ten years later. The juvenile court found that Matthew had not been prejudiced by the ten-year delay, even though it considered the delay unreasonable and unexplained. On October 6, 1998, the trial court issued a judgment declaring Matthew to be the biological father of the child. In December 1999, Matthew was ordered to pay current support of $338.94 per month and an arrearage of $44,960.09.
{¶ 4} Matthew filed a motion to extinguish the arrearage pursuant to amended R.C. 3111.13. In response, Shirley filed a complaint for declaratory relief, requesting the trial court to determine that R.C. 3111.13(F)(3) is unconstitutionally retroactive pursuant to Section 28, Article II of the Ohio Constitution. The trial court found the statute constitutional. Shirley appealed, and the court of appeals reversed, concluding that R.C. 3111.13(F)(3), as applied, violates Section 28, Article II of the Ohio Constitution.
{¶ 5} The cause is before this court upon the acceptance of a discretionary appeal.
II
{¶ 6} “Section 28, Article II of the Ohio Constitution prohibits the General Assembly from passing retroactive laws and protects vested rights from new legislative encroachments. Vogel v. Wells (1991), 57 Ohio St.3d 91, 99, 566 N.E.2d 154, 162. The retroactivity clause nullifies those new laws that ‘reach back and create new burdens, new duties, new obligations, or new liabilities not existing at the time [the statute becomes effective].’ (Bracketed material sic.) Miller v. Hixson (1901), 64 Ohio St. 39, 51, 59 N.E. 749, 752.” Bielat v. Bielat (2000), 87 Ohio St.3d 350, 352-353, 721 N.E.2d 28. To determine whether a law is unconstitutionally retroactive, we must first “determine whether the General Assembly expressly intended the statute to apply retroactively.” Id. at 353, 721 N.E.2d 28. If so, we must determine whether “the statute is substantive, rendering it unconstitutionally retroactive, as opposed to merely remedial.” (Emphasis sic.) Id. A substantive statute is one that “impairs vested rights, affects an accrued substantive right, or imposes new or additional burdens, duties, obligations, or liabilities as to a past transaction.” Id. at 354, 721 N.E.2d 28; Van Fossen v. Babcock & Wilcox Co. (1988), 36 Ohio St.3d 100, 106-107, 522 N.E.2d 489. A statute that applies retroactively and that is substantive violates *287Section 28, Article II of the Ohio Constitution. Bielat, 87 Ohio St.3d at 353, 721 N. E.2d 28.
{¶ 7} R.C. 3111.13(F)(3)(c) states:
{¶ 8} “A party is entitled to obtain modification of an existing order for arrearages under this division regardless of whether the judgment, court order, or administrative support order from which relief is sought was issued prior to, on, or after October 27, 2000.”
{¶ 9} Because the General Assembly expressly stated that a party is entitled to a modification of a judgment issued “prior to” the effective date of the statute’s amendment, it is unquestionable that the General Assembly intended this provision to apply retroactively. Therefore, we proceed to the second step of the retroactivity analysis, and examine whether R.C. 3111.13(F)(3)(a) is substantive.
{¶ 10} All parents have a duty to support their minor children. R.C. 3103.03(A); Haskins v. Bronzetti (1992), 64 Ohio St.3d 202, 203, 594 N.E.2d 582. See Pretzinger v. Pretzinger (1887), 45 Ohio St. 452, 458, 15 N.E. 471 (“The duty of the father to provide reasonably for the maintenance of his minor children, if he be of ability, is a principle of natural law”). The “ ‘wants and weaknesses of children render it necessary that some person maintains them, and the voice of nature has pointed out the parent as the most fit and proper person.’ ” Id., quoting 2 Com. 189. “[CJommon and statutory law in Ohio mandate that a parent provide sufficient support for his or her child.” Haskins, 64 Ohio St.3d at 205, 594 N.E.2d 582; State ex rel. Wright v. Indus. Comm. (1943), 141 Ohio St. 187, 25 O.O. 277, 47 N.E.2d 209, paragraph one of the syllabus; R.C. 3103.03(A).
{¶ 11} Matthew’s duty to support his child is manifest at common law and in statutory law. Moreover, and of the utmost significance to this case, Matthew’s duty to pay the child-support arrearage is memorialized by a court order that was issued prior to the amendment of R.C. 3111.13(F)(3)(a). We cannot but conclude that Shirley has a vested right in that court order. Any statute that impairs Shirley’s vested right is substantive. See Bielat, 87 Ohio St.3d at 354, 721 N.E.2d 28; Van Fossen, 36 Ohio St.3d at 106-107, 522 N.E.2d 489. We hold, therefore, that R.C. 3111.13(F)(3), as applied to this case, is unconstitutional because it would retroactively vacate the court order requiring Matthew to pay the arrearage in child support.
Judgment affirmed.
Moyer, C.J., Resnick and O’Connor, JJ., concur. Lundberg Stratton, O’Donnell and Lanzinger, JJ., dissent.