Kate Middleton celebrated her 31st birthday by watching the London showing of Cirque du Soleil with her family. A representative for the couple initially reported that the duchess would be spending her birthday privately, while another source hinted at a low-key celebration, but it turned out to be not so private as Middleton showed up in the very public show.

The pregnant Middleton was joined by husband Prince William, sister Pippa Middleton, brother James Middleton, and parents Carole and Michael Middleton. The group watched the Cirque du Soleil's acrobatic extravaganza "Kooza" from one of the private viewing boxes of the Royal Albert Hall.

Everyone seemed to be enjoying the show, especially when one of the clowns onstage, when his crown got stolen, pointed to the crowd and asked, "Who has my crown?" Middleton and her mom laughed as they glanced at Prince William, who giggled along with the mother and daughter upon getting the joke.

The group went to a private room during the intermission, the same one they came into when they first arrived for the 7:15 P.M. show. They stayed until the show ended at around 10:45 P.M., a little late for a pregnant woman to stay out but still quite early for Middleton considering she could very easily get home as she lives at Kensington Palace, which is just across the street from the Royal Albert Hall.