Angelina Jolie and Brad Pitt throw Knox and Vivienne fun 7th birthday party

It may be summer but Angelina Jolie and Brad Pitt's twins enjoyed some winter fun on their 7th birthday. Knox and Vivienne Jolie-Pitt celebrated their big day with their famous parents on Sunday at an ice rink.

The famous family, including Knox and Vivienne's older siblings, Maddox, 13, Pax, 11, Zahara, 10, and 9-year-old Shiloh, were spotted leaving Iceland Ice Skating Center in a suburb of Los Angeles on Sunday, all with big smiles on their faces.

"They rented a bus and headed for an afternoon of ice-skating," an eye witness told Us Weekly, adding that some of the twins' friends joined in on the fun. "Knox and Viv were bundled up with snow hats and mittens. They were really excited about it."

Photo: Getty Images

The onlooker added: "Everyone skated for about two hours and they tried out special bumper cars on the ice. They were spinning around getting dizzy and had a blast. Some of the kids were holding hands as they skated and it was really sweet."

The children were "wiped out" as they got back on the bus to go home. Despite her young age, Vivienne has already had one big role on the big screen. In Angelina’s 2014 film Maleficent, she played the young Princess Aurora, while her siblings Zahara and Pax had smaller walk-on parts.

"It had to be Viv," Angelina later explained to Entertainment Weekly. "The other three and four-year-old (actors) wouldn't come near me. It had to be a child that liked me and wasn't afraid of my horns and my eyes and my claws… When Pax saw me for the first time, he ran away and got upset."

Brad with his parents and their three oldest at Unbroken premiere Photo: Getty Images

Despite Viv’s strong acting genes, the actress was pleasantly surprised at how well her little one took to the role. Mother and daughter do have an especially close bond; Vivienne also likes to follow Angelina around. "She's always that kid, she's that little girl," Angelina told E! News last year. "We call her my shadow at home… The other kids are starting to get a little irritated about it!"

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