Could the Royal Baby be a Star Wars Baby? The Duchess of Cambridge, who was due to give birth around a week ago, will now have a May baby. Cue Star Wars fans everywhere hitting the bookies to put a bet on a May 4th Birthday…also known as Star Wars day. The unofficial celebration of all things Jedi takes place every year on May 4th, inspired by the pun 'May the 4th be with you'.