Katherine Heigl stars in the film Life As We Know It and just as her character has to adjust to a new life, Katherine and her husband Josh Kelley have had to do the same. Not only are they the new parents to daughter Naleigh, but Josh has had to learn how to deal with his wife kissing co-stars like Josh Duhamel!

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At the same time Katherine was becoming a mother on set in Life As We Know It, she became a mother to off-set as well!

“I thought I was going to be getting some advance training in how to be a real mother while I played the role in the movie. But the adoption of my baby from Korea went on ahead of schedule, and my daughter, Naleigh, arrived weeks before we began filming,” Katherine explained to Parade. “I was really thrown into hot water pretty quickly. I was sort of faking changing diapers on the set, but at home I was doing it for real.”

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While that was quite the adjustment for Katherine, her husband Josh was trying to adjust to Katherine locking-lips with her co-star!

“Actually, he and Josh Duhamel are good friends, but he would never come to the set when Josh and had to like kiss or make out. It does make him uncomfortable because he’s not an actor, he’s a musician,” she said. “He always says to me, ‘How would you feel if I had to make out with some girl in a video?’ And I’m like, ‘If you have to do it, you have to do it. But I wouldn’t want you to come home and tell me what a great kisser she is and I should try her technique.’ ”

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One technique Katherine has tried and decided to stick with is a way to help her quite smoking.

“Now I use an electronic cigarette. I know it’s ridiculous, but it’s helping me not to actually smoke real cigarettes. You feel like you are smoking, and you get to exhale but it’s just water vapor and not nicotine,” the actress explained. “I’ve been doing it for six months. Smoking sucks! The one thing I would say to my kid is, ‘It’s not just that it’s bad for you. Do you want to spend the rest of your life fighting a stupid addiction to a stupid thing that doesn’t even really give you a good buzz?'”

Life As We Know It hits theaters Friday!

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