Cate Blanchett adopts a baby girl

Cate Blanchett's family is growing.

The 45-year-old Oscar-winning actress just adopted a daughter with her husband, theater director Andrew Upton, her rep confirmed to People. According to Australia's Women's Weekly, the newborn's name is reportedly Vivienne.

The newest addition to the family joins Kate and Andrew's three sons, Ignatius Martin, 6, Roman Robert, 10, and Dashiell John, 13.

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"She's really excited and clearly besotted," a source tells Women's Weekly.

Though perhaps the news shouldn't come as too much of a surprise -- in June 2010, Blanchett told W magazine that she was definitely open to having more children.

"Everyone says, 'Oh, you must have [been trying] to have a girl,'" she shared. "If the next one was a boy, then that's just our lot! It's true you do get a bit demented [with three boys]. [But] the chaos of it is great."

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ET recently chatted with the Cinderella star at the film's premiere in Hollywood, where she revealed what her own magic wish would be. Watch below!