Mandatory Credit: Photo by Nils Jorgensen/REX/Shutterstock (9640214i) Catherine and the Duke of Cambridge with their new baby boy Catherine Duchess of Cambridge gives birth to her third child, Lindo Wing, St Mary's Hospital, London, UK - 23 Apr 2018 Catherine and the Duke of Cambridge at the Lindo Wing at St Mary's Hospital, Paddington, with their new baby boy, born at 11:01 BST today weighing 8lbs 7oz. is the third child of Catherine and the Duke of Cambridge, whose title will be HRH Prince of Cambridge, and will be fifth in line to the throne and the Queen's sixth great-grandchild.