Order unanimously reversed on the law without costs, in accordance with the following memorandum: Family Court erred in granting respondent father's CPLR 4401 motion to dismiss the mother's petition at the close of her evidence in a trial in which she sought an initial determination of custody of her three children. A full and complete hearing is required to determine, in the best interests of the children, which parent should have custody (Obey v. Degling, 37 N.Y.2d 768, 769-770; Matter of Blake v. Blake, 106 A.D.2d 916; Allen v. Kriesel, 87 A.D.2d 992). In addition, although the appointment of a Law Guardian is discretionary with respect to a Family Court Act article 6 custody petition (Family Ct Act § 249), it was an abuse of discretion for the court to have initially exercised its discretion to appoint a Law Guardian and then, when that Law Guardian apparently reported a conflict of interest, to have proceeded to trial without appointing a new Law Guardian and without providing, on the record, a rationale for having done so. If, as the court was informed by petitioner's attorney at oral argument, a divorce action is pending, then the custody issue should be resolved in that action. If such an action is not pending, then the case is remitted to Family Court for a plenary hearing before a different Judge. That Judge should exercise his discretion regarding the appointment of a Law Guardian.