The Queen's youngest grandchildren are the daughter and son of the Earl and Countess of Wessex. The Queen is known to get on well with their mother, Sophie, with whom she shares a love of riding, and the famliy lives near to Windsor Castle. It is said that Sophie frequently drops in to Windsor Castle after picking up the children from school for an impromptu visit with their grandmother.

In May 2011 the Queen released a touching picture of herself and her two youngest grandchildren riding ponies in Windsor Great Park. She is to be seen leading three-year-old James on a rein, while seven-year-old Louise sits confidently on her mount.

The Earl and Countess of Wessex have been very protective of their children's privacy, but they were delighted - and the Queen shared their joy - when seven-year-old Lady Louise Windsor was picked as one of the four bridesmaids at the wedding of Prince William and Catherine Middleton (picture above).

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