OPINION OF THE COURT
Weinstein, J.This appeal places before the court another of those unfortunate child custody disputes in which parents, in vying with each other for the privilege of having custody over the object of their mutual affections, engage in conduct which *73inevitably harms all parties, but most of all the innocent child. We are called upon to determine that course which will further the law’s well-settled mandate that the best interests of the child must always be paramount, as well as the equally well-established aversion to allowing a party to benefit from his own wrongful acts.
From 1966 until 1977, the petitioner mother and the respondent father lived together without benefit of marriage, while holding themselves out as husband and wife. On October 15,1970 the petitioner gave birth to a son, Marc, who is the subject of this proceeding. Two years later, the parties moved to Hammondsport, New York, and, five years after that, on October 7, 1977, they entered into what purported to be a separation agreement. This agreement falsely recited that the parties were legally married in Burlington, North Carolina, on November 5, 1966, and provided that petitioner would surrender title to any jointly held property and all rights to “alimony”. The agreement further stated that the petitioner relinquished custody of her son. Petitioner testified at a hearing that she had signed the agreement under duress and because the respondent had physically abused her, but it was respondent’s testimony that he did not recall striking the petitioner.
After the parties had separated, petitioner took up residence with Karl S., whom she subsequently married in February, 1978. Marc continued to live with the respondent pursuant to the agreement, but saw his mother every school day at the child’s school, where she was employed as a teacher’s assistant. In January, 1978 the respondent took a job in Danbury, Connecticut. He returned custody of Marc to the petitioner but visited him every three or four weeks. Unbeknownst to the petitioner, the respondent married Margaret P. on May 26, 1978. Thereafter, in June 1978, he told the petitioner that he wanted to enroll Marc in a day camp for two weeks. The petitioner agreed and permitted the respondent to take Marc for that purpose. The child was enrolled in a camp in Westchester County. When the child was not returned on the appointed date, the petitioner called the respondent. He told her that he was married and would never bring Marc back to her.
Petitioner thereupon commenced this proceeding to obtain *74legal custody of her son. The parties stipulated, pursuant to the Uniform Child Custody Jurisdiction Act (Domestic Relations Law, art 5-A), that the Family Court, Westchester County, would be the sole forum for this action, and they consented to the preparation of probation reports. It was further agreed that, while the Probation Department was conducting its investigation, the respondent would retain custody of Marc, with the petitioner having the right to call her son whenever she wished and the right of visitation every weekend from 6 p.m. Friday to 6 p.m. Sunday. Petitioner agreed that, if she failed to return Marc to the respondent at the stated time, she would “automatically forfeit * * * any further right to any visitation until further order of [the] court”. Petitioner testified that she had agreed to permit the respondent to retain custody of Marc during this period because she believed, as she had been informed by her attorney, that the custody hearing would be held within four to six weeks.
The Probation Department in fact took nearly six months to complete its investigation. Throughout this time, the petitioner, her husband and, on occasion, her parents visited Marc every other weekend. Due to the distance between the parties’ residences, they drove through the night, picked him up on Saturday morning, and stayed with him at a motel. Eventually, the petitioner became “frustrated” with this arrangement and, consequently, on January 20, 1979, she took Marc back home with her to Hammondsport. On February 2, 1979 the Family Court ordered the petitioner to return the child to the respondent, and she promptly complied. Thereafter, the respondent would not permit the petitioner to see or speak with her son.
In its report dated March 16, 1979, the Westchester County Probation Department recommended against disturbing the custodial arrangement then in effect. The recommendation was based in part upon an evaluation by a County Department of Community Mental Health psychiatrist who found that the respondent and his wife were more stable than the petitioner and her husband. This psychiatrist prepared his report without ever having interviewed the petitioner and her husband or learning anything about the petitioner; he based his conclusions solely upon the respon*75dent’s biased description of the petitioner’s life-style. Another psychiatrist, from the Steuben County Mental Health Clinic, interviewed the petitioner and found her to be “a normal woman with the logical concerns at this moment about the future of her relationship with her son.” This psychiatrist noted that the petitioner “seems to have settled and established a close relationship with her husband, a person of steady and respectable background (head of the mathematics department of the [school system] where he has worked for 17 years).”
On or about March 31, 1979, shortly after the Probation Department completed its report but before the custody hearing commenced, the respondent moved his family to Deerfield Beach, Florida. He did so without leave of or application to any court, and without notifying the petitioner. In Florida, he obtained an unlisted telephone number and, as a result, the petitioner was compelled to bring a writ of habeas corpus to regain access to her son. On June 6, 1979 the Family Court ordered the respondent to disclose his telephone number and to permit the petitioner to speak to her son by telephone. But even then, respondent continued to interfere with petitioner’s efforts to talk to the boy. Petitioner called Florida some 76 times, but was permitted to speak with her son on only three occasions.
The hearing in the matter was finally commenced on June 27, 1979. In addition to evidence of the foregoing events, testimony was taken from respondent and his wife as to their good relationship with Marc. Dr. Abraham Halpern, a private psychiatrist who was retained by the respondent, testified that Marc had a good relationship with relatives of the respondent’s wife in Florida. He testified further that moving Marc to a new home would have a deleterious effect because it would be “a great disadvantage for the youngster to be moved to another home, no matter how good * * * the new setting might be.” Dr. Halpern’s conclusions, as was the case with those of the Westchester County psychiatrist, were formulated without interviewing the petitioner or her husband and without conducting any investigation of the conditions in their home.
On August 15, 1979 the court awarded custody to the *76respondent, with visitation to the petitioner, inter alia, for one month in the summer. In support of its determination, the court reasoned that: (1) it is important for children to have “a minimum of disruption in their living arrangements in their early, formative years”; (2) the private psychiatrist testified that “a change in custody at this time would be detrimental to the child’s well-being”; and (3) “[f]rom the testimony elicited at the hearing, the Court is left with the impression that there is more stability in the father’s home”. It is from this determination that the petitioner now appeals. We reverse.
There was, as the dissent suggests, a certain degree of conflict in the evidence presented at the hearing, and we agree that in such cases, and indeed in all custody proceedings, due deference must be accorded to the trial court, which has seen and evaluated the evidence first hand (see Bunim v Bunim, 298 NY 391, 393). Nevertheless, the overriding concern where custody is in issue must be the best interests of the child (see Domestic Relations Law, §§70, 240; Obey v Degling, 37 NY2d 768; Matter of Bennett v Jeffreys, 40 NY2d 543; Matter of Barry W. v Barbara K., 55 AD2d 607). An appellate court would be seriously remiss if, simply in deference to the finding of a Trial Judge, it allowed a custody determination to stand where it lacks a sound and substantial basis in the record and, indeed, is contrary to the weight of the credible evidence (cf. Matter of Darlene T., 28 NY2d 391, 395). We find such to be the case at bar.
At the outset, there is no credible support in the record for the Family Court’s finding that there is more stability in the respondent’s home than in the petitioner’s. The one psychiatrist who so found reached that conclusion without ever having interviewed the petitioner, and based his findings solely upon the respondent’s biased evaluation of the petitioner’s style of life. Opinions formulated upon such one-sided and biased information are virtually valueless. And the same can be said of the findings of Dr. Halpern. Having been retained by the respondent and having similarly had the benefit only of biased, second-hand information, Dr. Halpern’s conclusions would appear to be *77based on something less than an objective, professional evaluation.
Hence, the Family Court relied heavily on professional opinions of dubious probative worth while apparently ignoring, as does the dissent, the significance of the respondent’s personal conduct—conduct as to which there is little, if any, dispute. The record seems clear that, throughout the struggle over who should have custody of Marc, the petitioner has demonstrated a far greater willingness to respect the visitation rights of the noncustodial parent than has the respondent. We find it highly significant that during the period from January until June, 1978, when petitioner had physical custody of Marc, she amicably agreed to overnight visitation, while respondent generally permitted contact between mother and child only when explicitly ordered to do so by the court. Particularly egregious is the respondent’s surreptitious departure with Marc to Florida without leave of or application to any court (cf. Walsh v Walsh, 64 AD2d 980). There he obtained an unlisted telephone number which he refused to divulge until ordered to do so by the court. And even then, he caused the petitioner’s efforts to contact her son by telephone to be almost invariably unsuccessful. It is clear that as between the parties, petitioner is more capable of respecting the visitation rights of the noncustodial parent.
The dissent passes over these acts, noting only that the respondent’s move to Florida did not violate any court order and did not require prior leave of the court. Although that may be so, the record is plain that the move was in large part a knowing and calculated effort to cut off, or at least to impede, the petitioner’s right of access to her son. We have stated in no uncertain terms that the very act of interfering with visitation between young children and their natural parents is “so inconsistent with the best interests of the children as to, per se, raise a strong probability that the [offending party] is unfit to act as custodial parent” (Entwistle v Entwistle, 61 AD2d 380, 384-385, app dsmd 44 NY2d 851). On the other hand, petitioner has shown that she loves Marc and, as the Family Court found, has not been an unfit mother in any way. In our view, the course of conduct engaged in by the respondent has clearly shown *78him to be less fit than the petitioner to act as custodial parent. Moreover, although the stability of a child’s living arrangements is certainly a legitimate consideration in any custody proceeding (see Matter of Nehra v Uhlar, 43 NY2d 242, 249-250; Dintruff v McGreevy, 34 NY2d 887, 888), we cannot say that returning 10-year-old Marc to Hammondsport, where he spent some six years of his life, would be as disruptive to him as was his removal, by deception, to Westchester County, and then his subsequent surreptitious move to Florida with its consequent interruption of his contact with his mother. If there has been interference with the stability of Marc’s living arrangements, respondent must take the blame.
Finally, we acknowledge the dissenter’s legitimate concern that custody disputes be promptly resolved with finality. Nevertheless, we refuse to exalt the desirability of a solution qua solution at the cost of the best interests and welfare of the child. The courts are commanded by law and by sound considerations of policy to find not merely a solution, but the best solution in terms of the welfare of the child. Where, in our view, a court has failed to do so, we will not hesitate to take appropriate remedial action on appeal (see Thomas J. D. v Catherine K. D., 79 AD2d 1015).
Accordingly, we reverse and award custody to the petitioner. As there is no dispute over the fact that the respondent is the child’s father, we remit the case for the purpose of entering an order of filiation as well as to fix appropriate visitation for the respondent.