Sir William de Warenne - John de Warenne's issue

There seem to be too many brothers and sisters on this profile
Here are the correct children
Children of John de Warenne, 6 th Earl of Surrey:

and Alice de Lusignan had three children:

Eleanor, who married Henry Percy and was the mother of Henry de Percy, 1st Baron Percy of Alnwick; (See Percy Family)
Isabella, who married John Balliol (also called John II Baiol) and was the mother of Edward Balliol;
William, who married Joan, daughter of Robert de Vere, 5th Earl of Oxford, and was accidentally killed at a tournament on 15 December 1286. Their son John succeeded his grandfather as earl of Surrey; their daughter Alice de Warenne married Edmund Fitzalan, 9th Earl of Arundel.

William also seems to have too many children. He died at 30. He had only 2 children ( above). Could someone correct this please?