The Vita Adelheidis names "Gerbirg…filia ducis Godefridi" as wife of "Megengoz". The Memorial of "Megendaudus…Gerbirga marito" also names "Irmendrudis", recording that she was born with them, presumably indicating that she was their daughter, with the name "Adelheidis abbatissa" recorded at the end of the passage out of context. 1
Marriage Information:
Gerberge married Gf. Megingoz IV VON AVALGAU. (Megingoz IV VON AVALGAU died after 29 Apr 989.)
Sources
1 Foundations for Medieval Genealogy, Medlands, Gerberga.