Exclusive: Sienna Miller Welcomes 2nd Child with Boyfriend Oli Green

Sienna Miller has given birth to her second child, MailOnline can exclusively reveal.

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Sienna, 42, welcomed a baby girl with her boyfriend Oli Green, 27,

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And was seen stepping out for the 1st time with her new arrival on Wednesday.

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She already has daughter Marlowe, 10,

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From her earlier relationship with actor Tom Sturridge, 38.

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Sienna's pregnancy was revealed during a beach holiday

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In August where she stepped out sporting a bump.

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She revealed: 'I was very fortunate.

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I wasn't necessarily trying to get pregnant.

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This happened as a total surprise and biologically was something I was able to do.'

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