She became the Duchess of York and Albany by marrying James, Duke of York in 1660 when she was visibly pregnant.
She had her first child with James out of wedlock before they married in 1660.
Her marriage to James was seen as highly controversial because she was the daughter of a commoner and publicly displayed her affection for the Duke.
She suffered from advanced breast cancer and died shortly after giving birth to her son, Edgar.
She was the mother of Mary II of England, who shared power with her husband William II from 1689 to 1694.