William II Chatelain de St. Omer
William II Chatelain de was born about 1090 in St Omer, Pas-de-Calais, France.  He died about 1143.

 Melisende de Picquigny
Melisende de was born about 1090 in Picquigny, Picardy, France.  Melisende de is no longer alive.

 Mahaut de St. Omer
Mahaut de was born in 1110 in St Omer, Pas-de-Calais, France.

 William III Chatelain de St. Omer
William III Chatelain de was born about 1120 in St. Omer, France.  He died in 1170.