Liev Schreiber has become a father for a third time.

The 55-year-old actor and his girlfriend Taylor Neisen welcomed their first child together into the world, daughter Hazel Bee, on August 27th, and the 'Ray Donovan' star is "so happy".

He wrote on Instagram: "So happy that Hazel Bee is finally here. She arrived early in the morning of August 27th and has been a dream every day since."

The 'X-Men Origins: Wolverine' actor revealed both Hazel and Taylor are "super happy and healthy".

He added: "Mom and baby are both super happy and healthy. Thanks to all for the love and support."

Liev and Taylor were first romantically linked in 2017 and since confirmed their romance with several red carpet appearances.

The actor and director has sons Sasha, 16, and Kai, 14, with his ex, actress Naomi Watts, who married The Morning Show's Billy Crudup in June.

Liev and Naomi announced in August 2016 they had gone their separate ways after 11 years together.

In a joint statement, the former couple said: "Over the past few months we've come to the conclusion that the best way forward for us as a family is to separate as a couple.

"It is with great love, respect and friendship in our hearts that we look forward to raising our children together and exploring this new phase of our relationship. While we appreciate your curiosity and support, we ask the press to be mindful of our children and respect their right to privacy."

Naomi previously told how she used to always ask Liev for career advice.

She said: "We're both interested in each other's work. And we ask each other for advice, I trust his judgement and I like to think he trusts mine. I could be wrong.

"It's about supporting the other. When both parents are in the creative arts, it's not nine-to-five. Sometimes our schedules mean we spend a lot more time at home than most parents. And then there are times we have to travel for long periods.

"If one of us feels very passionately about a job, the other supports and takes over. That's the nature of the profession. But we always make it work."