A Palace source told The People: "When she saw William playing a game after lunch at Sandringham she thought the Nintendo looked tremendous fun and begged to join in.

"She played a simple ten-pin bowling game and by all accounts was a natural.

"It was hilarious. William was in fits of laughter. He was enormously impressed at having such a cool gran.

"And although she is 81 the Queen's hand-eye co-ordination was as good as somebody half her age."