Aaron Johnson has become a father for the second time.

His fiancee Sam Taylor-Wood gave birth to a baby girl earlier this month, joining their 18-month-old daughter Wylda Rae, although a name for the newborn is not yet known.

Aaron, 21, and his director partner, 44, met on the set of John Lennon biopic 'Nowhere Boy' in 2009 and became engaged the same year.

It is a fourth daughter for Sam, as she already has Anjelica, 14 and Jessie, five from her marriage to art dealer Jay Jopling - who was once romantically linked with Lily Allen.

Aaron has previously defended the couple against critics who say the 23-year age gap between them is too big.

He said: "I'm in love, I'm blissfully content. No one's getting hurt. We're in a loving relationship. We're engaged. Everyone who matters is happy. Exactly which bit of that do I have to defend or apologise for?"

Speaking before the birth of Wylda, the actor revealed how he had always wanted to Settle down and have a family.

He said: "I've always been really up for a baby, I knew very early on - we were very much in love, and it was something that I wanted... It came from me, but maybe it took her to want me to want one. I wanted to be grounded, to surround our kids with love. I love the two girls [Sam's daughters], I love them to bits, I want the family, and I think that's what she's always wanted."