The Duke and Duchess of Cambridge, Prince William and Kate Middleton, are expecting their third child, a statement from the Kensington Palace confirmed. The announcement was made on Monday after Kate had to cancel a royal engagement because of morning sickness. The news has come as a surprise to many as there was little indication that the 35-year-old royal was pregnant.According to news agencies, as with her other two pregnancies, the Duchess is suffering from Hyperemesis Gravidarum, a form of severe morning sickness, and was forced to cancel her engagements Monday. “The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child. The Queen and members of both families are delighted with the news,” the palace said in a statement.Usually a royal pregnancy is announced at 12 weeks, but because of the Hyperemesis Gravidarum, the missive was sent out ahead of schedule as she had to miss some official engagements. Kate is being cared for at Kensington Palace.The royal couple already has two children, Prince George, 4, and Princess Charlotte, 2. George is expected to start school at Thomas’ Battersea, a private institution in South London, this week.Kate had earlier dropped a hint about her third child during a trip to Poland last month. When she was presented with a gift for newborns, she said, “We will just have to have more babies”. Even at that time, many started speculating that a new royal baby could be on its way, and it seems they just needed to wait a month for the official confirmation.