Old School vs. New in Billy & Bette's New Movie

Often times the best movies are the ones that come from personal experiences, and that's just what Billy Crystal mined for his new comedy with Bette Midler, Parental Guidance. Get a first look behind the scenes!

Video: Watch the 'Parental Guidance' Trailer 

Inspired by his own real-life experience of being asked to babysit his daughter's kids for several days, Billy says he immediately cranked out a story after all the mishaps and misunderstandings he endured: "It became a real contemporary story about old school vs. new school, about how I as a parent parented, and how my daughter is parenting now -- and our conflicts about doing that."

In theaters Christmas Day, Parental Guidance casts Billy as Artie, a grandfather who's used to calling the shots. When his eager-to-please wife Diane (played by Bette) agrees to babysit their three grandkids -- much to Artie's chagrin -- modern problems collide with Artie and Diane's old school methods of tough rules. But despite the numerous problems that come up -- yielding hilarious comedic dividends -- the family ultimately learns that they can come together by embracing the best of both worlds. Marisa Tomei and Tom Everett Scott also play the kids' type-A helicopter parents.

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"It's a human story told in a very funny and sweet way," says Bette. "I think everybody's in this film -- we've all clashed with our parents … we've all been treated well or badly, we all have vulnerabilities, we've all tried really, really hard to accomplish something and either succeeded or failed at it. It's a human experience."