Eva Mendes knew Ryan Gosling wanted a baby

Eva Mendes and Ryan Gosling's unborn baby "has been a long time coming."

Eva Mendes and Ryan Gosling Source: Bang Showbiz

The 40-year-old actress, who is set to give birth to their first child in October, reportedly decided to start a family with the heartthrob because she knew how much the Gangster Squad star, 33, wanted to experience fatherhood.

A source told PEOPLE magazine: "This has been a long time coming. Ryan and Eva definitely discussed children before. She knows how much he wants to be a dad and he's going to be an amazing father."

The couple, who live in The Notebook star's modest home in Studio City, Los Angeles managed to keep the actress' pregnancy a secret until recently by only telling a few close friends and family members.

An insider revealed: "[She] just hasn't ever wanted anyone beyond her close friends and family knowing more than they had to. And Ryan is certainly private and always has been."

The Hitch beauty has also "barely left the house" since she found out she is pregnant in a bid to keep the news under-wraps.

The source added: "Their lives completely changed as soon as Eva got pregnant. They used to travel all over the place together and go on hikes with their dogs.

"Ryan has been taking care of her, picking up food and running errands. He has been very supportive about keeping things a secret."