In this proceeding, which is here on cross appeals, we are to construe the payment provisions of two trust indentures executed by the settlor, Lewis McComb Herzog, Sr., coincident with an agreement of separation entered into between him and his then wife, Angela Stevenson Morgan, petitioner-appellant. The trust indentures bear even date, are identical in terms and were created for the purpose of securing covenants for the separate support of the wife and infant issue of the marriage, as provided in the separation agreement. Before proceeding to a discussion of the controverted payment clause, certain undisputed facts should be mentioned.
Petitioner-appellant and respondent-appellant were married in New York City, June 7, 1928. The daughter, Angela, was born in 1930 and the son, Lewis, Jr., in 1932. Unhappy differences developed leading to a separation and the execution of the aforementioned agreement of separation under date of June 28,1933. This agreement made provision for a financial settlement which, briefly, provided the sum of $5,000 per annum payable monthly for the wife’s separate support until she remarried, and the sum of $2,500 payable in monthly installments to the wife for the maintenance, education and support of each of the infant children during minority except that, when the children were in the custody of the father, payments to the wife were to cease except for a proportionate rental value of the home maintained by her for herself and the children. To secure these payments three separate trusts in the principal sum of $125,000 each were established, one for the wife with which we are not concerned (for it terminated upon the remarriage of the wife in 1938, and its principal was added to the trusts for each of the children in equal shares) and two trusts equal in amount and identical in terms for the benefit of each of the children. It is these latter two trust deeds that have our attention. The United States Trust Company of New York was named trustee in each instrument.
*132Following the establishment of the trusts the wife was duly-appointed guardian of the person, and the trust company was appointed guardian of the property, of each of the infants. Such appointments continue in effect. In 1935, the wife instituted proceedings in Nevada for absolute divorce based on cruelty, in which the husband appeared by attorney. A valid decree of divorce was obtained which incorporated the terms of the prior separation agreement in haec verba.
Subsequently both parties remarried and are now living with their respective spouses, the petitioner in New York City, and the respondent in the State of Florida where he has established a legal residence and maintained his domicile since 1941. In 1940, the wife refused to allow the father custody of the children during the July-August vacation period, resulting in a habeas corpus proceeding instituted by the father which was eventually terminated in a ruling by this court to the effect that a modification of the custody provision of the prior agreement of separation was unwarranted (People ex rel. Herzog v. Morgan, 287 N. Y. 317). Prior to and subsequent to this ruling, from June 28,1933, and down to July 1,1945, the parties observed a condition of the separation agreement providing for income payments to the wife during the period she has custody of the children, approximately nine and one-half months of each year, and to the father for the vacation periods for the remainder of the time. In July, 1945, the children, then fourteen and twelve years of age, and at the time in the custody of the father at his home in Florida, pursuant to the separation agreement, decided not to return to the mother in New York, but elected to remain with the father in Florida. Because of the children’s expressed preference to remain with him, the father instituted proceeding's in the State of Florida for a modification of the custody arrangement and for payment of the trust income to him while he had custody. The wife, in various motions including a habeas corpus proceeding, attacked the jurisdiction of the Florida court and when all had been resolved against her, appeared generally in the action and controverted the issues at a trial. This resulted in a final judgment, modifying the custody provisions so that the position of the parties was reversed, the father being awarded the main custody for nine and one-half months and the mother for the vacation period of two and one-*133half months of each year. The Florida court also ordered the wife to pay the trust income received by her to the father during the period he had custody. In the meantime the bank stopped all payments to anyone and has accumulated the income. The father has provided for the children’s maintenance and support in what has been described as a lavish and extravagant manner.
The within separate proceedings were commenced by the wife as guardian of the person of each of the infant children, to construe the income payment provisions of the respective trust indentures for the benefit of each child and for other relief, including major custody. Her prayer for custody has been abandoned and only the payment provisions are now controverted on the ground that she is entitled to payments as guardian under the express terms of the trust indenture which may not be altered by any independent modification of the terms of the separation agreement, and on the further ground that it expressly provided that it was to be construed and administered under the laws of the State of New York. The husband, in his opposing answer, joins in the application for construction, urging that the payments should be made to him while the children are in his custody because the primary purpose of the trust indenture was to secure the financial settlement for the benefit of the children as provided in the separation agreement. The trust company, in its answer, also joins in the application for construction but remains otherwise neutral. The special guardian also filed an answer in which he too asked for a construction and incidental relief. The controverted provisions of the trust directed the trustee to hold, manage and collect the income and, after payment of all necessary expenses, “ to pay the net income thereof to the extent of Two thousand five hundred (2,500) Dollars per annum during the minority of the said Lewis McComb Herzog, Jr. to Angela Stevenson Herzog in equal monthly instalments to be applied by her as guardian of the person for the maintenance, education and support of said Lewis McComb Herzog, Jr.; provided, however, that if the Grantor shall at any time be called upon to pay and discharge any debt or liability created or incurred by said Angela Stevenson Herzog for account of the said Lewis McComb Herzog, Jr., the Trustee shall out of said net income of Two thousand five hundred (2,500) Dollars reimburse the *134Grantor for any payments so made as provided in said separation agreement, and so accumulate the balance of the said income until said Lewis McComb Herzog, Jr. attains the age of twenty-one years, and upon that event to pay over the said accumulated income to said Lewis McComb Herzog, Jr., provided, however, that there shall be paid by the Trustee out of said accumulated or surplus income, when sufficient for the purpose, all bills for school tuition, board and extras incurred in the education of the said Lewis McComb Herzog, Jr., which said bills shall be rendered to and paid by the Trustee and be subject to its supervision and control.
“ After the said Lewis McComb Herzog, Jr. attains the age of twenty-one years, the Trustee shall pay the net income to him during his life in equal monthly instalments.”
It is also provided that, upon the death of the son, Lewis, the corpus be paid over to whomever the son should appoint, or, if the power of appointment be not exercised, the corpus be paid to Angela (the daughter) in the event he leaves no issue or, if he leaves issue, then to the surviving issue per stirpes. The trust deed for the benefit of the daughter, Angela, uses identical language except for appropriate changes.
In the preamble of each trust indenture reference is made to the separation agreement “ bearing even date ” in which the grantor covenanted to make certain payments for the benefit of the infant (either Angela or Lewis, Jr.) and that he was desirous of securing said payments, etc. This, we believe, justifies reference thereto in our search for the answer to the construction problem. For convenience we turn to the separation agreement. It makes provision for the father’s visitation while the children are in the custody of the mother at certain designated times and places and then provides: ‘ ‘ During the months of July and August, or such parts thereof as he shall request, and during the period of the Easter school vacation if he shall so desire, the party of the first part [the father] shall have the right to have the care, custody and control of the said children and during the period of such custody, if requested by the party of the first part [the father], the fixed payments to be made to the party of the second part [the mother] for the support and maintenance of the said children shall cease except the proportionate part of the rental of the *135home maintained by the party of the second part as a home for herself and said children, and during such period the party of the first part [the father] shall be entitled to apply to their maintenance and support the balance of the fixed income for such period which would ordinarily be payable to the party of the second part from the trust funds created for the benefit of said children.”
It also provided that in the event the father was called upon to pay and discharge any debt or liability incurred by the mother for the account of the children, the father was to be paid out of the income of the trust fund for the benefit of the child for whom such payment is made.
The lower court has construed the controverted provision of the trust deed to mean that monthly payment of the income derived from each trust to the extent of $2,500 shall be paid to the mother as guardian, in proportion ‘ ‘ to such time of each year as petitioner actually has custody ” and that any excess shall be accumulated for the benefit of the ¿respective infant until he or she shall have attained his or her majority and tha no payments were to be made to the father.
The Appellate Division affirmed by a divided court, the dissenting Justices voting to modify so as to direct payment to the father of the sum of $2,500 for each of the minor children to be used by him for the support of the children, according to the separation agreement, for such time as he has their legal custody. We are in accord with the view expressed by the dissenting Justices below.
This is a construction problem. In resolving it primary attention must be given to the manifest purpose sought to be accomplished. When this is ascertained it will take precedence over all other canons of construction (Farmers’ Loan & Trust Co. v. Callan, 246 N. Y. 481; Matter of Buechner, 226 N. Y. 440; Robinson v. Martin, 200 N. Y. 159; Mullarky v. Sullivan, 136 N. Y. 227). In seeking such purpose and intent we are not limited under the circumstances of this case to the language of the trust indenture. It must be read in connection with the separation agreement executed under even date. Both such instruments made reference to the other and together constitute part of a single financial plan “ instinct with obligation ” to provide a fixed monthly income for the support of the infant children *136during minority, in lieu of and in complete satisfaction of the father’s obligation in the premises. These instruments, as we read them, are not mutually exclusive in terms and obligations but are interrelated and being interdependent must be read together. Neither can successfully stand alone. If either is to be considered separately and one accorded a position of precedence over the other that precedence must be accorded to the separation agreement. Until it was executed there was no need for the creation of a trust. When created its express purpose was to furnish security for the unconditional performance by the settlor of his covenant to provide support for his infant children. The provisions of both instruments must be examined and, if necessary, read as one to ascertain the purpose and intent (65 C. J., Trusts, § 247, p. 500). Manifestly, there was but a single purpose — security for the children’s support. This must be made effectual. Substance must not be destroyed in deference to the naked word (Wood v. Duff-Gordon, 222 N. Y. 88). The trust indenture directs the trustee to make income payments to the wife “ to be applied by her as guardian * * * for the * * * support ” of the infants. The wife had no individual interest in such payments. The husband’s obligation for her separate support, pending remarriage, had been fully discharged in a separately created trust. Her position then “ as guardian ” is but an extension of the trustee’s obligation to apply money for the benefit of the infant children. She was, for all intents and purposes, a subtrustee for the accomplishment of a single purpose. The word “ guardian ” under such circumstances need not be regarded as requiring unyielding obedience as the recipient of income payments. It is a mere word of designation of the person or party in position to carry out the primary cardinal purpose, which in either instance ostensibly means the support of the children while in the custody of either parent. The parties, as a matter of fact, have so construed the income payment provision from the date of execution of the separation, agreement and the implementing trust indenture of 1933 down to July 1, 1945, by payments to the father when he had custody during the two and one-half months of the vacation period. This was in recognition of the' income payment terms contained in the separation agreement — because a similar clause was not incorporated in the trust indenture is no reason for limiting its payment of income derived from *137the trust to the mother as guardian. The parties placed a practical construction on the arrangement which may not he ignored. To say that the language of the underlying instrument is paramount and controlling over the primary agreement it was designed to implement is to exalt language over substance and work an unwarranted forfeiture of a clearly discernible purpose. It is axiomatic that the law does not favor forfeiture or penalties but strives to effectuate the purpose and intent which may be gathered not only from the instrument itself but from the circumstances surrounding its making and its expressed purpose and intent. The mere naked provision in the trust indenture requiring the trustee to pay the income to the mother as guardian must yield in the light of actual circumstances and in this instance custody is a very compelling circumstance. It is true that the parties failed to anticipate a change in custody — and in particular that such change would come about by the modification order of a court of competent jurisdiction after a trial of the issues. Nonetheless such has happened and the parties are bound by the Florida decree. We cannot disturb it and accordingly we must take it as we find it — a modus operandi between the parties governing the custody of the children. The Florida decree, however, in this instance, cannot operate to change the trustee’s duties in the controverted trust indenture. Neither it nor the res were subject to the jurisdiction of the Florida court and its decree directing the mother to pay the father an appropriate amount of the trust income while he has custody of the children, insofar as the trustee is concerned, is without effect and it has so treated it by refusing to make payments to any one and, pending direction, has accumulated the income in both trusts. The valid modification of the custody provisions of the separation agreement has reversed the position of the parties — the father now having the major custody and that of the mother being limited to the vacation period. Obviously, the mother, as guardian, except for a limited period, cannot apply the trust income in the manner provided, nor does she claim that she is entitled to such payments on any basis except the single circumstance that the trust indenture designated payment to her as guardian and that her appointment as such has not been vacated. As we see it, the determinative factor is whether the income is to be available for the cestuis.
*138Authority is ample for the proposition that a court in the exercise of its equitable powers may control the administration of a trust so as to effectuate its avowed purpose, particularly when changing circumstances would otherwise defeat it (e.g., see authorities collected in 2 Scott on Trusts, § 167; 4 Pomeroy’s Equity Jurisprudence [5th ed.], § 1309.). This trust was created by the father, out of his personal funds, in fulfillment of his obligation in the premises. Under such circumstances even though the father has ample means, as is the case here, to support said children without any need for the income derived from the trust, it nevertheless should be made available to him during the period of his custody irrespective of any other consideration. This is particularly so when infant beneficiaries are involved and the named recipient of the trust income refuses to apply the income as intended, or is in a position where she is unable to so apply it. In either case the. .purpose of the trust is nullified or thwarted, which eventuality the court will prevent by appropriating the income to the declared objective (Oberndorf v. Farmers’ Loan & Trust Co., 208 N. Y. 367). It is the avowed purpose of the payments rather than the method that is controlling.
The orders should be modified in accordance with the opinion herein, and as so modified affirmed, with costs to the respondent-appellant, Lewis McComb Herzog, Sr., payable out of the funds and the matter remitted to the Special Term for further proceedings not inconsistent with this opinion.