The actress said that she has to keep them in mind when deciding whether or not to take on a particular role, because she wouldn't want to spend long away from them.
"So many different things factor into that one decision," Watts told the Los Angeles Times, when asked how she chooses her roles. "Sadly, a lot of it today is about time and place and length of shoot, you know?"
"Because now I'm a mum and I have to answer those questions," Watts continued, referring to her husband and fellow actor Liev Schreiber and their two children.
"And then of course, it has to be about the filmmaker and his vision," the actress added.
Watts claimed that her recent role in the drama Mother and Child was one of the favourites of her career because her character was so varied.
"She was complicated and beautiful," Watts said. "And bitchy and sexy, and all those things. I just loved her."
Watts was nominated for 'Best Supporting Actress' at this weekend's Independent Spirit Awards for her role in the film, but lost out to Dale Dickey for Winter's Bone.