Actress Sienna Miller, 42, welcomes second child with her boyfriend Oli Green, 27, (Photos)

British-American actress, Sienna Miller has given birth to her second child.

The actress, 42, who welcomed a baby girl with her younger boyfriend Oli Green, 27, was spotted for the first time with her new arrival on Wednesday January 3.

She already has a daughter Marlowe, 10, from her previous relationship with actor Tom Sturridge, 38.

Sienna’s pregnancy was revealed during a beach holiday in August when she revealed her baby bump.

In December Sienna covered Vogue as she spoke for the first time about her pregnancy and revealed she was having a girl.

Sienna spoke candidly about her pregnancy and how it had been ‘unplanned’, but admitted she feels ‘more psychologically prepared’ than with her first born.

During the rare interview, Sienna said that Marlowe has been angling for a sibling for some time.

Sienna also said she’d been fighting her own prejudices about being an older mother and has to learn to stop making a joke out of it.

She told the publication: ‘I’d love to get to a point where I didn’t feel the need to make a joke of my being older and having a baby, to show I’m in on the joke.’

And in a video she filmed with Vogue, Sienna revealed that the pregnancy was an unplanned one.

She revealed: ‘I was very fortunate. I wasn’t necessarily trying to get pregnant. This happened as a total surprise and biologically was something I was able to do.’

Sienna went on to further address the stigma around pregnancy as an older woman as she has fought her own prejudices around the subject.

 
She added: ‘I think people are comfortable with a way of living that has existed for many years, which is very misogynistic and patriarchal.

‘Like me being the older woman in a partnership with a younger person or being pregnant over 40 and that that’s irresponsible and poor child and it’s such double standards.’