Now that Gwen and Angelina's families are staying in London, the two A-listers are constantly setting up play dates for their kids and getting close by the day.

The 36-year-old actress and the 41-year-old singer have been getting closer, especially now that their families are both residing in London at the moment. Yesterday, Jolie was spotted with her children, Zahara, 6, Shiloh, 4, and twins Vivienne and Knox, 3, with Stefani and his 5-year-old son, Kingston, outside Gwen's home in London for a fun-filled playdate.

It was said that Gwen and her rocker husband, Gavin Rossdale, are close friends of Brad Pitt for a long time. Pitt and ex-wife Jennifer Aniston even attended Stefani and Rossdale's wedding in 2002, and is said to be running around the same circle of friends since then. When Pitt started to go steady with Jolie, the rock and roll couple embraced the change and that was when Stefani got to be friends with Angelina. This is a huge change, since Jolie has never seen with a "BFF" material because like what she said in the past, she doesn't have a lot of friends.

"I talk to Brad, but I don't know. I don't have a lot of friends I talk to. He is really the only person I talk to," said Jolie to CNN last year. Another reason why Stefani and Jolie are close is the coincidental similarity of the time they get pregnant with their children. Jolie gave birth to her twins just a month before Stefani had their son, Zuma.

"Somehow (Gwen and I) keep ending up pregnant at the exact same time, were having a playdate and Gwen was trying to figure out what she was going to wear as she got more pregnant... I asked her if she had any spare clothes, and she gave me this (L.A.M.B.) dress" Jolie told the Sydney Morning Herald back in 2008. Another source added that not only are Jolie and Stefani close, but their children seem to be getting along as well.

"All of the kids are very close in age. They've attended each other's birthday parties and gotten together several times at each other's homes," said a source to Yahoo news.

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