Geofroy IV De Mayenne
Geofroy IV De was born about 1140.  He died about 1169.

 Isabelle De Meullent De Beaumont
She died on May 10th, 1220.

 Juhel III De Mayenne
Juhel III De was born about 1170 in France.  He died in 1220 in Albigeois battle.