The Duchess of Cambridge has given birth to her second child with Prince William - a baby girl.

The Kensington Palace official Twitter announced the news at 11.10am this morning posting, "Her Royal Highness The Duchess of Cambridge was safely delivered of a daughter at 8.34am."

The baby girl weighs 8lbs 3oz and both mother and child are doing well.

It was announced early this morning that the Duchess was in labour with the Kensington Palance twitter revealing, "HRH The Duchess of Cambridge was admitted at 06.00hrs to St Mary’s Hospital, Paddington, London and is in the early stages of labour."

They later tweeted, "The Duchess travelled by car from Kensington Palace to the Lindo Wing at St. Mary’s Hospital with The Duke of Cambridge."

The Duke and Duchess already have one son together, Prince George, who was born in July 2013. They celebrated their fourth wedding anniversary on April 29.

Check out our favourite Prince George moments here.