http://en.wikipedia.org/wiki/Adele_of_Vermandois

Adele of Vermandois was a daughter of Herbert II of Vermandois with his first wife, Adela. She married Count Arnulf I of Flanders in 934 and had four children:
▪ Luitgard, married Wichmann, Count of Ghent
▪ Egbert, died 953
▪ Baldwin III of Flanders
▪ Elftrude, married Siegfried, Count of Guînes
Through her descendants Matilda of Flanders and Henry I of England, she was an ancestor to the present-day British royal family.