(dissenting in part). The primary concern of a court in determining an application for modification of child support payments is the best interests of the child. (Matter of *157Brescia v Fitts, 56 NY2d 132, 141; Matter of Boden v Boden, 42 NY2d 210, 212.) Since the trial court properly considered the best interests of the child in vacating the provisions of the separation agreement and divorce judgment, directing payment of $500 per month for child support, and ordering instead payments of $850 per month, I would affirm that portion of the judgment of Justice Wolin appealed from.
It is undisputed that there has been a profound change in the defendant’s financial circumstances since the time of the execution, in 1976, of the separation agreement that provided for his monthly support payments for the infant child. In 1980, defendant realized $3.1 million in cash from the sale of his shares of stock in his business.
The trial court, in addition, found that "based upon the testimony and evidence introduced * * * the present amount of child support paid by defendant is inadequate. The child, Jordan Rubin, is now an adolescent with expanding interests and needs, e.g., summer camps, religious instruction, and additional tutoring and education”. These expanding needs of an adolescent certainly contrast with those that could reasonably be anticipated by the parties when executing the separation agreement at a time when the child was three years old.
For these two reasons — the expanding unanticipated needs of the child and the ability of the defendant to easily meet those needs by virtue of the substantial increase in his financial means — I find that the trial court properly vacated the terms of the separation agreement and increased the defendant’s child support obligations.
The majority’s determination that the provisions of the separation agreement should not be disturbed is, in my view, based upon too narrow a reading of the leading Boden and Brescia cases.
In Matter of Boden v Boden (42 NY2d 210), the Court of Appeals held that despite the existence of a separation agreement setting forth provisions pertaining to the support of the children of the marriage, an action could be commenced on behalf of the child for an increase in support. The court held (p 212) that the "key consideration” is "the best interest of the child” and that, if the facts and circumstances of the case show an unforeseen change in the parent’s circumstances and an increased need of the child, an increase in support would be warranted.
While the opinion in Matter of Brescia v Fitts (56 NY2d 132) *158manifests some concern about "the broad reading given our decision in Boden by some lower courts” (p 138), the Court of Appeals clearly reaffirmed the principle that in the appropriate case an increase in child support payments may be ordered notwithstanding the existence of a separation agreement (56 NY2d, at pp 140-141). Among the factors that the court indicated should be considered by the lower courts in reaching a determination as to whether a modification in support is warranted are "the increased needs of the children due to special circumstances or to the additional activities of growing children” and "a substantial improvement in the financial condition of a parent” (supra, at p 141) — two factors that are specifically present here and which were given careful and appropriate consideration by the court below in exercising its discretion. (See also, e.g., Verrone v Voegtle, 103 AD2d 1005.) That court’s determination that increased support from the defendant would be in the best interest of Jordan Rubin and his growing adolescent needs should not be disturbed.
Sandler and Kassal, JJ., concur with Lynch, J.; Murphy, P. J., and Ellerin, J., dissent in part in an opinion by Ellerin, J.
Judgment, Supreme Court, New York County, entered on or about May 23, 1985, reversed to the extent appealed from, on the law, without costs and without disbursements, and the amended complaint dismissed, and the order of said court entered on December 2, 1985, and its implementing judgment of March 20, 1986, modified, on the law, only to the extent of vacating the award of child support arrears and the attorney’s fees previously awarded and, as so modified, affirmed, without costs and without disbursements.