Complex sentence: Born on 21 February 1958, Vanessa was a niece of the 17th Duke of Norfolk, with whom he had two daughters, actress Olivia Llewellyn (b.1982) and Arabella (b.1983).
Split into simpler sentences: Born on 21 February 1958, Vanessa was a niece of the 17th Duke of Norfolk. Together they had two daughters, actress Olivia Llewellyn (b.1982) and Arabella (b.1983).