*William de Ferrers 3rd Earl of Derby
born about 1120 Derbyshire, England

father:
*Robert de Ferrers (Ferrieres) 2nd Earl of Derby
born about 1090 Derbyshire, England
died 1141 Merevale, Warwickshire, England
buried Abbey of Merevale, Warwickshire, England

mother:
unknown

siblings:
Petronilla Ferrers

spouse:
*Margaret Peverel
born about 1114 Nottingham, Nottinghamshire, England
married about 1135 Nottinghamshire, England

children:
*William (Robert?) de Ferrers, 4th Earl of Derby born 1144 Derby, Derbyshire, England
died 21 October 1190 Seige of Acre, Jerusalem, Palestine
buried Normandy, France
Wacheline de Ferreres born about 1140 Oakham, Rutlandshire, England

biographical and/or anecdotal:
He was known as a favorite of King John, from whom he received large grants of land, among which was the great Northampton estate of William Pevrel, whose daughter one of his ancestors married. Earl William was largely instrumental in placing Henry II. on the throne and took an important part in the siege of Mount Sorrel and the battle of Lincoln. In 1230 he was one of the three chief counselors recommended to the king by the barons.

notes or source:
LDS