Julia Roberts says her husband is her "rock".

The Hollywood actress constantly relies on the support of her cameraman spouse Daniel Moder - with whom she has three children, five-year-old twins Hazel and Phinnaeus and son Henry, three - and has praised him as a husband and father.

She said: "He's my rock. My husband is my best bud. He's so smart and he never lets me down."

Julia also admits she wouldn't be able to accept as many movie roles as she currently does if it wasn't for Daniel being willing to take on as much responsibility as he does for raising their kids.

She added in an interview with Style magazine: "People often ask me about balancing work and motherhood and whatnot, but it's easier for me than for so many others. I can choose when I work and I have a wonderful support system in place."

Julia, 42, insists there is no "magic trick" to having a happy marriage, you just have to build your relationship on love and mutual respect.

She explained: "There's no 'secret' to a successful marriage - it's not a magic trick - I'm just lucky to have found someone who I can build my life on.

"I'm at an appropriate place in my life. But you have to continually nurture that place. I don't think it's a finite fixed point on a map, but family definitely plays a huge part in that."