Research Notes:
The Oxford Dictionary of National Biography states, [1]
Seagrave married first Rohesia, daughter of Thomas and sister of Hugh Despenser, and second Ida, also called Ela, sister of Henry Hastings, who in 1247 was fined £500 for an unlicensed second marriage with Hugh Pecche. He had three sons: John (d. 1231), the eldest, who married Emma, daughter and heir of Roger de Caux; Gilbert of Seagrave (d. 1254), who succeeded him; and Stephen; he also had a daughter, Eleanor.
[1] William Hunt, revised by Paul Brand, "Seagrave [Segrave], Sir Stephen of (d. 1241)," Oxford Dictionary of National Biography (Oxford University Press, 2004, online edition), [Oxford_Dictionary_National_Biography], [OxfordDNB(UM)].