At the beginning of this month The Duke and Duchess of Cambridge announced the very exciting news that they are expecting a third child.
They try to be protective of their privacy, especially when it comes to their children, George, 4, and Charlotte, 2 and because of this the public don't know very much about the young Prince and Princess.
However Prince William has recently given more of an insight into the lives of his children.
As William toured Aintree University Hospital in Liverpool, he revealed Princess Charlotte is following in Prince George's confident footsteps, saying: "George rules the roost and Charlotte isn't far behind."
When speaking about Charlotte he also admitted: "I think she's going to be trouble when she's older - all fathers say that."
Last week William hinted that Kate might be further along in her pregnancy than people thought.