Henry III's half sister (The concise dictionary of national biography. Part 1 : from the beginnings till 1900. London : Oxford University Press, 1969, pg. 1367).
McBride www site has his first wife as Alice Brun, 2nd Joan Mowbray (WWW site Paul B. McBride's genalogy page (http://www.tiac.net/users/pmcbride/james/f024.htm).