Olivia Wilde and fiancé Jason Sudeikis have announced the birth of their son – and revealed that they've chosen the babyname Otis.

The US actress, best known for her role in Tron: Legacy, tweeted the news alongside the very first picture of her baby.

“Ladies and gentlemen," she posted, "Otis Alexander Sudeikis has LEFT the building! (I'm the building).”

Well, that’s one way to put it!

In the black-and-white pic, the newborn is snuggling into his smiling mum's neck.

Olivia, 30, only announced she was expecting her first child in October and said her due date was 4 May – so it seems Otis has arrived just a little early.

Congratulations!

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