Whenever a guardian ad litem shall be appointed for a person under disability as defined in this act or an infant, incompetent or conservatee shall appear by his guardian, committee, or conservator, respectively, or where such appointment is not required under or is dispensed with pursuant to power conferred by this act the proceeding shall be binding upon such person to the same extent as if such person was under no disability.
N.Y. Surr. Ct. Proc. Act Law § 406