In the Autumn of 1647 Mary suffered a miscarriage, after which she couldn't conceive for several years. In early 1650, she was pregnant again. In late October-early November, when the princess's pregnancy was coming to an end, her husband fell ill with smallpox and died on 6 November, just after his attempt to capture Amsterdam from his political opponents; two days before his death, on the day of her nineteenth birthday, Mary gave birth to a son, William. The newborn prince's cradle was draped with black cloth as a sign of sorrow for his father. Since the titles of the stadtholder of the Netherlands and the Prince of Orange were not inheritable, little William didn't receive them immediately after birth.