Aaron Paul is banned from saying the word "breathe" during his wife's labour.
The 'Breaking Bad' star and wife Lauren are expecting their first child imminently, and have hired a doula - a trained birth companion - to help them through their daughter's arrival.
Aaron, 38, told 'Jimmy Kimmel Live!': "We got a doula, I had no idea what a doula was but she's teaching us some stuff. She said, 'First thing you need to know is never say the word relax and don't ever say breathe.' She said that my wife would most likely hit me if I do. She's just telling me what not to do."
But while the 'Path' star and his wife have made preparations for the birth, they are yet to decide on a name for their baby girl.
Aaron revealed: "We have a few, a few names. If one of us didn't like one of the names it never made it into the pile. We have a handful of names and we're going to name her once we meet her."
Lauren, 31, is due "any minute now", and the actor admitted he is very excited about becoming a father.
He said: "I'm over the moon excited. I love babies, I've always loved babies."
Aaron added: "We just hang out in our nursery a lot. It's our favourite room of the house, and yeah, everything's ready."
The couple met at the Coachella music festival in California and married in 2013.
Aaron recently took to social media to praise Lauren as a "gift to this planet" on her 31st birthday.
He posted a picture of her showing off her burgeoning baby bump and said: "Happiest of birthdays to this mother to be. Can't wait for this precious little baby girl to be in our arms my love. What a gift you are to this planet. I love you thru the stars and back. Enjoy the day. (sic)"
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