Prince William left the King Edward VII Hospital in London this evening. He was visiting Kate Middleton, who was admitted for an acute form of morning sickness called hyperemesis gravidarum. The palace confirmed Kate's pregnancy this morning after weeks of speculation. She has since canceled multiple upcoming appearances in order to rest. Kate was out and about in recent days, though, attending St. Andrew's Day celebrations at her former school, traveling to Cambridge with William, and appearing at a reception at London's Natural History Museum.