People around the world get very, very excited whenever a royal baby is on the way.
And thanks to the Duchess of Cambridge and Meghan Markle we've had four senior royal babies in the last few years.
During the pregnancy there's always lots of speculation about whether it will be a girl or a boy, the name and when he or she will be born.
There's also a lot of chat about what the new little prince or princess might look like, and some hardcore fans have even used prediction websites to get an idea work.
Using a photo of mum and dad, the sites create an image of what the couple's child could look like.
But the results for Princess Charlotte were far from accurate.
Little Charlotte, who is fourth in line to the throne, was born on May 2, 2015 to the delight of royal fans around the world.
She made history when her brother Prince Louis was born as she became the first woman in history to keep her place in the line of succession despite having a younger male sibling.
Last week Kate and William announced that Charlotte will be attending the same school as her big brother Prince George in September.
She will start at Thomas's Battersea in south London in September - a private school which will cost the Duke and Duchess of Cambridge £18,915 a year.
Simon O'Malley, headmaster at Thomas's Battersea, said: "We are delighted that the Duke and Duchess of Cambridge have decided that Princess Charlotte will join her elder brother, Prince George, at Thomas's Battersea.
"We greatly look forward to welcoming her and all of our new pupils to the school in September."
Charlotte, who turned four earlier this month, has been attending Willcocks Nursery in Kensington since last January.
