Princess Charlotte celebrates her sixth birthday

A photograph of a smiling Princess Charlotte has been released to mark her sixth birthday on Sunday.

The picture was taken by her mother, the Duchess of Cambridge, this weekend in Norfolk.

Princess Charlotte is fourth in line to the throne.

Catherine and William marked their 10th wedding anniversary on Thursday by releasing a video of Charlotte with her brothers George, seven and Louis, three.

It showed the family at a beach and toasting marshmallows near their Norfolk residence, Anmer Hall.

In the new photo, Charlotte is pictured outdoors wearing a dark blue short-sleeved dress with a floral design.

For her last birthday, her parents released a picture of Charlotte volunteering with the rest of the family by helping to load a van with food and delivering meals to those in need in Norfolk.

She was born at the private maternity Lindo Wing of St Mary's Hospital in Paddington, central London, at 08:34 BST on 2 May 2015, weighing 8lb 3oz.

Her mother, Catherine, is a keen amateur photographer and patron of the Royal Photographic Society. Her pictures have regularly been released to mark her children's birthdays.