N.Y. SCP Law § 402

§ 402. Appearance for infant, incompetent, conservatee or person under\n disability\n 1. An infant may appear by the guardian of his property, an\nincompetent by the committee of his property, and a conservatee by his\nconservator. The appointment of a guardian ad litem does not bar the\nguardian, committee or conservator from appearing as a party. The\nperson so appearing and his attorney shall each file on or before the\nreturn day of process an affidavit showing\n (a) that he is qualified to protect their rights,\n (b) whether he is related to or connected in business with any party\nto the proceeding or the attorney for any party,\n (c) whether he is entitled to share in the estate in which the\ninfant, incompetent or conservatee is interested or is in any way\ninterested therein,\n (d) whether he has any interest adverse to or in conflict with that\nof the infant, incompetent or conservatee and\n (e) such additional facts as may be required by the court.\n 2. A person under disability shall appear by a guardian ad litem\nwhere no appearance is made as provided in subdivision one or where the\ncourt so directs because of possible adversity or conflict of interest\nor for other cause.\n