This is a proceeding to permanently deprive parents of their custodial rights to their infant child under the provisions of 33 V.S.A. § 656. As a consequence of an altercation occurring at one of the hearings, the father was committed to Waterbury State Hospital and determined to be insane at the time of the hearing. Since no guardian was appointed to protect this parent’s interest in a proceeding involving so vital a right, the resulting judgment cannot stand and a new hearing must be had. See Billings v. Billings, 123 Vt. 324, 326, 187 A.2d 333 (1963).

Judgment vacated and cause remanded.