Complex sentence: Dame Cynthia Mary Sergison Brooke, Viscountess Brookeborough, DBE, the daughter of Captain and Mrs. Charles Warden Sergison, married Viscount Brookeborough (9 June 1888-18 August 1973), son of Sir Arthur Douglas Brooke, 4th Bt.
Split into simpler sentences: Dame Cynthia Mary Sergison Brooke, Viscountess Brookeborough, was the daughter of Captain and Mrs. Charles Warden Sergison. She married Viscount Brookeborough (9 June 1888-18 August 1973), son of Sir Arthur Douglas Brooke, 4th Bt.