According to "History of Newport Pagnell":
"Gervase married Isabel, daughter of Robert Earl of Leicester and widow of Simon St Liz Earl of Northampton, by whom he had issue of one son Robert, who predeceased him leaving no issue. His sister Hawyse survived him, however, and became his heiress."
"By her first marriage with John de Somery the Barony of Dudley, of which Newport was a member,passed into the hands of the Somery family, who appear to have anciently had aBarony in Cambridgeshire."