Duchess Kate and Prince William are expanding the family! Kensington Palace revealed today the couple is expecting their third child -- the Palace posted a statement on Twitter: "Their royal Highnesses 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 press department for the royal family went on to post a full statement about Kate's physical well-being and that, as with her first two pregnancies, she is suffering from hyperemesis gravidarum, aka morning sickness, and that her planned public appearances would be cancelled.

The couple have son George, 4, and Charlotte, 2. Prince George is set to start school on Sept. 7 at Thomas' Battersea in south London. Kate and Will are expected to accompany their kindergartener to school on day 1, where they will be met by the school's headmistress and will be escorted to their son's classroom.

Oh, and check out Prince Harry commenting on the news!