The couple, who are already proud parents of their firstborn son Prince George, 14 months, have finally passed the critical first trimester.
Mom-to-be Kate has suffered from hyperemesis gravidarum, a serious form of morning sickness, for the first three months of her pregnacy. But while still fragile, the Duchess appears to be leaving the worst of her sickness behind her at last.
"Their Royal Highnesses The Duke and Duchess of Cambridge are delighted to confirm they are expecting a baby in April 2015," the Palace announced in a statement. "The Duchess of Cambridge continues to be affected by Hyperemesis Gravidarum, but her condition is steadily improving."
So much so, in fact, that plans for her to attend the Singapore Prime Minister's state visit tomorrow are scheduled to go ahead as anticipated, marking Kate's first public appearance since her second pregnancy was announced.
The pregnant Duchess will greet the President of the Republic of Singapore and Mrs. Tony Tan Keng Yam with her husband, Prince William, at London's Royal Garden Hotel before traveling with the President and Mrs. Tan to Horse Guards Parade, where the President will receive a Ceremonial Welcome.
All going well, later in the day, an eager Kate will also attend the Wildlife Photographer of the Year 2014 Awards Ceremony at the Natural History Museum.
Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!