 His wife was Dubhdara ingen Cellaig, daughter of Cellach mac Cerbaill and sister of Donnchad mac Cellaig, both kings of Osraige.Melkorka Mýrkjartansdóttir, whose story is told in the Icelandic Laxdæla saga, claimed to be the daughter of Muirchertach.Melkorka was sold as a slave to the Icelandic chieftain Höskuldur Dala-Kollsson, with whom she had an illegitimate son named Ólafur “Pái” Höskuldsson.