The Mortimer Family
Elizabeth Mortimer was daughter of Lady Philippa Plantagenet and Edmund Mortimer, Earl of March.
Lady Philippa Plantagenet
Roger Mortimer, 1st Baron Mortimer of Chirk
Eleanor de Clare (Eleanor de la Zouche) was married to William la Zouche, 1st Baron Zouche of Mortimer (from the research of John Lloyd Marlow)
Wikipedia says about William la Zouche:
Joyce Zouche (Botetourt) was the daughter of William la Zouche according to John Marlow but this does not show on the Wikipedia page. There is also a reference to the Battle of Bannockburn and the wars of Scotish independance. Another Botetourt cross-reference.