Aaron Johnson and Sam Taylor-Wood

Kick-Ass star Aaron Johnson and his fiancée, director Sam Taylor-Wood, have welcomed a baby girl.

Taylor-Wood gave birth to Wylda Rae on Wednesday in London, the couple said in a statement.

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This is the first child for Taylor-Wood, 43, and Johnson, 20, who met on the set of her 2009 directorial debut, Nowhere Boy, in which Johnson played a young John Lennon. Taylor-Wood has two daughters from her first marriage to art dealer Jay Jopling.

Taylor-Wood and Johnson announced their engagement in October and their pregnancy in January.

In April, Taylor-Wood, who has battled colon cancer and breast cancer, defended the pair's age difference and said she ignores any judgment about it.

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"The amount of men I know with the same age gap that we have — how come no one says anything about that? It's totally sexist," she told Harper's Bazaar. "I try to ignore it. In my life, I've never really listened to when people start forming opinions on how you should be doing things."