In In re Marriage of Halpern (1982) 133 Cal. App. 3d 297, a child was born during the marriage. When the parties filed for dissolution, it was alleged the child was of the marriage. When husband sought increased visitation, wife filed an amended petition claiming the child was not of the marriage and indicating that she was involved in a new relationship with a man who wished to adopt the child. ( Id. at pp. 302-303.) Subsequent tissue tests showed that husband could not be the biological father. ( Id. at p. 302.) Husband claimed wife was estopped to deny he was the natural father or a de facto parent to the child. ( Id. at p. 313.) The appellate court disagreed, and permitted wife to challenge the husband's status as a father. ( Id. at p. 314.)