Catherine was the daughter of Jean Tristan de Maignelay and Marie du Jouy-en-Josas. The date and place of her birth have not been found.
Her husband was Jean Sorel. They were married, but the date and place have not been found. Their five known children were Agnès (c1422-1450), Charles (<1428-?), Louis (?-?), André (?-?) and Jean (?-?).