Who was the brother of XXX?
Hedvig Sophia of Sweden
Between 1697 and 1699, there was a Danish policy to create an alliance with Sweden through a double wedding between Charles XII of Sweden and Princess Sophia Hedwig of Denmark, and Prince Charles of Denmark and Hedvig Sophia of Sweden (after the marriage of Hedvig Sophia in 1698, she was replaced by Ulrika Eleonora of Sweden).
Charles XII of Sweden