Complex sentence: Her paternal grandparents were Reginald Grey, 2nd Baron Grey de Ruthyn and Alianore Le Strange of Blackmere, and her maternal grandparents were Thomas de Ros, 5th Baron de Ros and Beatrice Stafford.
Split into simpler sentences: Her paternal grandparents were Reginald Grey, 2nd Baron Grey de Ruthyn and Alianore Le Strange of Blackmere. Her maternal grandparents were Thomas de Ros, 5th Baron de Ros and Beatrice Stafford.