Garner stars in the fantasy family film "The Odd Life of Timothy Green," opening on Wednesday in U.S. movie theaters, in which she teams with Australian actor Joel Edgerton ("The Warrior") to play a small town couple who have given up on their dream to have a child of their own.

When they bury a box in their garden containing all their written wishes for child, a young boy named Timothy (CJ Adams) shows up on their doorstep and has a profound impact not just on his new family, but the entire town as well.

Garner, 40, sat down with Reuters to talk about the film, and what it's like to balance work with her family - husband Ben Affleck, daughters Violet, 6, and Seraphina, 3, and five-month old Samuel.

Q: You rarely play a full-time mom in movies. What made you say yes to this?

A: "That was kind of on purpose. I was nervous about merging the two - the real part of me and the work part of me."

Q: Worried how? That you'd be pigeon-holed in that light?

A: "Right. And I'm kind of seen that way in life, which I loathe, but which is reality."

Q: You mean because of all the paparazzi photos of you with your children?

A: "The last thing you want to do is play into that or exacerbate that in any way. But this role, I campaigned for it. I really went after it. This role was so right on so many levels - the messiness (of parenting), the humiliation and how a kid can humble you. How you work so hard toward some imaginary goal in your mind and then realize it's out of synch with what's best for the child."

Q: Did you feel especially motherly toward the young boy?

A: "How can you not? Joel and I took on very parental roles. Joel would play soccer with him, keep him occupied and laughing. I would make sure he had a bathroom break or a snack. Joel and I realized we're in it with his kid. (To this day) I text his mom! I'm tied to him as long as he wants to be tied to me."

Q: Two months after you wrapped shooting, you got pregnant for the third time, with your first boy. The magic from this film may have birthed this boy for you.

A: "I have to say, I feel the same way. I'm shocked that I had a boy. We had not thought in our minds that we would have a boy. I feel like he is a little bit magic. But he's only five months and I'm so in baby lust right now, that I feel like he has to be magic."

Q: Were you consciously trying for a third?

A: "We were in discussions. We could have stopped it, but this (film) might have pushed us over the edge to have another. It's so life affirming, this movie. It really made me feel like, Gosh, if I could go through this again, why wouldn't I? And Ben is just really agreeable! (laughs)"

Q: How did you guys balance family and work on this movie?

A: "Ben took a break. We found a school (on location in Georgia) and he did drop off and pick up. He did bedtime and brought them to see me almost every day. He was great ... .This was a movie I couldn't say no to, so we all did it and were better for it."

Q: How so?

A: "The kids became more self-sufficient, they became closer to Ben. We decided to have another baby and he's great. So nothing but good has come from this."

Q: Any thoughts of going back to work?

A: "I feel like I've gotten pickier with (the birth) of each child. I haven't worked in 15 months but now I know I want to go back to work."

Q: How's that?

A: "Ben is making a movie in Puerto Rico and I went to visit. There were a bunch of crew members that I knew. I was chatting with them and one guy was talking about a fight scene I had done. I was like, a fight? I couldn't even fathom! It made me wistful. I made me feel like, 'OK, I'm ready. It's time.'"

(Reporting By Zorianna Kit, Editing by Jill Serjeant and Doina Chiacu)

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