OPINION OF THE COURT
Ross, J.The instant appeal raises the issue of whether the doctrine of res judicata should be applied to a determination of the Family Court, which held valid the child support provisions of a separation agreement.
On October 2, 1969, in New York City, plaintiff Joan Moore Casson married defendant Phillip Casson, who is a physician. Thereafter, a daughter, Christina, was born in April 1970. Subsequently, the parties executed a separation agreement (agreement), dated October 5,1970; and then, less than a month *343later, defendant husband went to Mexico and obtained a judgment of divorce, dated October 24, 1970, which judgment incorporated by reference but did not merge, the provisions of this agreement.
Under paragraph 7 of that agreement, while sole custody of the child has been given to the plaintiff, the defendant has been permitted reasonable visitation privileges.
The defendant’s obligation to provide for the child’s financial needs is spelled out in detail in paragraph 9 of the subject agreement, which is entitled: “support, maintenance, and education of child.” This paragraph contains three subdivisions, a through c, and, pursuant to them, defendant is, inter alia, required, in pertinent part:
(a) to pay $500 per month for support and maintenance;
(b) to increase the monthly support and maintenance payment, mentioned in (a), by the “additional sum of Fifty ($50.00) Dollars per month for each Five Thousand ($5,000.00) Dollars net after taxes earned by the Husband in excess of Thirty Thousand ($30,000.00) Dollars per annum commencing with the year 1970”; and,
(c) to pay education expenses “from kindergarten school through college”, and the plaintiff is to have the sole discretion to determine if the child is to be sent to private school or schools.
In May 1982, plaintiff commenced the instant action in the Supreme Court, New York County, to recover on the child’s behalf, alleged arrears from the defendant. According to the complaint, the defendant owes: (1) based upon the formula set forth in subdivision (b), additional support and maintenance for the last six years, since defendant’s earnings have increased; and, (2) pursuant to subdivision (c), five years of private school tuition payments, in the sum of $12,275, plus interest.
Defendant answered, and in his seventh affirmative defense and counterclaim he asserts, in substance, that: “The Separation Agreement, and in particular the provisions dealing with tuition payments and increase of support based upon defendant’s earnings, are unfair and inequitable when made and at present.”
Following the joinder of issue, plaintiff moved to, inter alia, strike this seventh affirmative defense and counterclaim, upon the ground of the doctrine of res judicata, since this exact issue of whether the agreement was “unfair and inequitable when made” had been previously raised as a defense by defendant in a Family Court proceeding between the parties, and that issue *344had been resolved against him, in an order/judgment (one paper) of the Family Court, New York County (Phillip B. Thurston, J.), entered July 21,1977, which granted summary judgment to the plaintiff-petitioner for child support arrears of $500 per month for six months in the total amount of $3,000. Subsequently, we unanimously affirmed, without opinion, this Family Court order/judgment (61 AD2d 893 [1st Dept 1978]).
The plaintiff, as petitioner, initiated this earlier Family Court proceeding to collect from defendant the monthly support and maintenance due the child, pursuant to subdivision (a) of paragraph 9.
Even though a copy of defendant’s answer is not contained in the instant record on appeal, the records of this court contain a copy, in view of the fact that, as mentioned supra, the Family Court result was appealed to us (appeal number 1764 of January 1978). It is hornbook law that “a court may take judicial notice of its own records (Richardson, Evidence [10th ed], § 652)” (Weinberg v Hillbrae Bldrs., 58 AD2d 546 [1st Dept 1977]). Thus, we will make reference in this opinion to relevant documents in that prior record on appeal, and now a part of our official records.
Although only support and maintenance arrears were being sought in the Family Court proceeding, defendant in the first affirmative defense of his answer put in issue the validity of the entire agreement. In the fourth paragraph of that answer, defendant contended, in pertinent part, that he was not liable for child support since “an invalid separation agreement [was] procured by petitioner’s [plaintiff’s] duress and fraud committed upon respondent [defendant], and such separation agreement was also unconscionable and overreaching as to the respondent [defendant] at the time it was made.” Furthermore, in this particular affirmative defense, which consisted of nine separate paragraphs, the defendant asserted, inter alia, that he only married the plaintiff because she accused him of making her pregnant with Christina, and that he only signed the subject agreement when “petitioner [plaintiff] threatened that if respondent [defendant] did not sign the * * * agreement in the form presented, she would raise a problem with the immigration authorities as to respondent’s [defendant’s] moral character and respondent [defendant] would not be able to obtain United States citizenship and would be forced to leave this country” (note: this quotation comes from the tenth paragraph of defendant’s answer).
*345After receiving defendant-respondent’s answer, plaintiff-petitioner moved for, inter alia, summary judgment. As mentioned supra, the Family Court granted petitioner’s motion; and, thus, rejected defendant’s attack on the validity of the agreement. Incidentally, on appeal before us from this Family Court determination, defendant-respondent apparently gave up his contention that the agreement was not valid since he did not raise it in either his main or reply briefs. The two arguments made by defendant-respondent to us were that Family Court allegedly erred by: (1) denying him a hearing concerning plaintiff-petitioner’s means and ability to contribute to the support of the child; and, (2) denying him an opportunity to prove that he is not the father of the child by a blood-grouping test.
In the instant action, Special Term granted plaintiff’s motion to dismiss defendant’s seventh affirmative defense and counterclaim, upon the doctrine of res judicata.
Based upon our comparison of defendant’s seventh affirmative defense and counterclaim in the instant action with defendant’s first affirmative defense in the prior Family Court action, we agree with Special Term’s application of res judicata, since the issue, in substance, was the same: was the separation agreement invalid, due to its allegedly being unfair and unequitable, as a result of plaintiff’s overreaching? Defendant fully litigated this issue in the Family Court and it was resolved against him. As we unanimously stated in Mutual Fire, Mar. & Inland Ins. Co. v James & Co. (92 AD2d 203, 208 [1st Dept 1983], affd 61 NY2d 680 [1984]), “[j]ustice and fairness precludes the [defendant] from again litigating [this] same issue”.
The contention of the dissent that the sole matter before the Family Court was the recovery of “arrears in support under paragraph 9 (a) of the agreement” is not justified by an examination of the record in that proceeding, since that position completely ignores the defendant’s assertion of his first affirmative defense, which put into issue the validity of all of the provisions of the separation agreement, including the provisions dealing with support and maintenance.
Furthermore, the dissent’s statement that because the Family Court lacks equity jurisdiction, it cannot “set aside or modify the terms of the separation agreement” misperceives the powers of the Family Court. (Cf. Matter of Brescia v Fitts, 56 NY2d 132, 139 [1982].)
Accordingly, the order, Supreme Court, New York County (Hortense Gabel, J.), entered November 18, 1983 which, inter alia, granted plaintiff’s motion dismissing defendant’s seventh *346affirmative defense and counterclaim, should be affirmed, without costs.