Sire Bertrand de Gavre
Bertrand was born about 1129 in Gavere, Flandre-Orientale, Belgium.  He died in 1150.

 Ida Domnison de Chievres
Ida Domnison was born in Chievres, Hainault, Belgium.  She died after 1176.

 Bertha de Gavre
Bertha was born about 1144 in Gavere, Flandre-Orientale, Belgium.