Mandy Moore, Onscreen Sisters Bond While Bidding On eBay

Romantic comedy 'Because I Said So' shows just how overbearing moms can be.

PACIFIC PALISADES, California — The sun is shining down on Mandy Moore, her feet planted firmly in the green lawn adjacent to a sprawling cliff-side estate hundreds of feet above the Pacific Ocean's lapping waves.

Straightening out her dress, she feels the eyes of more than a hundred assembled guests on her while she sneaks a glance at the three-tiered wedding cake, the awaiting band, a photographer and an officiant eager to hear "I do."

Before you go alerting the tabloids, know that her beau, Zach Braff, is nowhere to be seen. Instead, Moore is standing in the middle of this idyllic wedding scene while filming her upcoming romantic comedy, "Because I Said So."

"I haven't been to a lot of weddings in real life," the 21-year-old actress said. "For all of us girls, we get to get it out of our systems. [Movie] weddings are a little bigger and more elaborate than what we would choose to have."

Maybe so, but most girls' weddings won't have Piper Perabo ("Coyote Ugly"), Lauren Graham ("Gilmore Girls") and Oscar winner Diane Keaton in attendance. It's also doubtful their proceedings will unfold with as much clever detail and heart-tugging hilarity as "Because," the offspring of an unusual union between the writers of "Stepmom" and "Heathers" director Michael Lehmann.

"I play Milly Wilder. I have my own catering company, and God, how do I explain this?" Moore said. "Basically, I'm the youngest of three daughters and my mother, played by Diane Keaton, is really intent on trying to get me to settle down with the right guy, because I have the habit of falling for the wrong kind of men. So the movie is about her trying to find a relationship, a steady relationship, for me to be in, and she goes to great lengths to try and find these men. One route that she decides to take is Internet dating."

 Mandy Moore on "Because I Said So"
 Photos from the set of "Because I Said So"
 In Focus: Mandy Moore
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The writers of the film got the idea when they saw a real-life site with a parent auctioning off an unlucky-in-love adult child. "I hope it wasn't my dad!" Perabo said. "Yikes!"

"I just really love my fake sisters, Mandy and Piper," Graham added. "We've had a really wonderful time. We talk about our eBay purchases."

"Not just do they look like they could be sisters, but they feel like they could be sisters," Lehmann said. "We've encouraged them to spend time together. Most of the time, I think they search on eBay and do shopping and discuss things that have no meaning to me whatsoever."

"I do like eBay a little bit," Perabo said. "We like all the same stuff kinda. The three of us oddly have similar tastes, so I was like, 'Oh my gosh, did you see such-and-such?' "

"I remember that being one of our first conversations where we were like, 'And do you do the thing where you watch the item?' " Graham said. "I can't tell you what [items], 'cause then other bidders will go and say, 'It's them!' and jack up the price."

In the movie, Moore's Milly endures a series of failed relationships with the help of her family, whose opinions are never more than a cell-phone conference call away. In one of today's scenes, her confused caterer phones in from a bathroom, soliciting their outrageous assessment of a potential one-night stand.

"We start the movie off on a great note," Moore said. "It's just the cute, funny rapport and conversations you have with your sisters and your mom, while sort of being appalled by what's being said."

"Lauren plays the oldest daughter, and she's the one who holds the whole family together," Perabo said. "Mandy's the youngest, and she's a little unsure of herself and is looking for a guy. ... I'm Diane's daughter May, and I'm sort of the sexy, rebel daughter. A little bit oversexed, maybe."

The stars' relationships in real life mirror what will be seen on the big screen.

"I love the mother/daughter story, and I feel like the relationship that I have with Diane in this movie echoes the relationship that I have with my mom," Moore said. "My mom's not trying to set me up with people or marry me off or anything, but this movie is great in exploring the complex relationships that are mother/daughter relationships. How sometimes your mom just makes you wanna pull your hair out, but you love her at the end of the day, and you know she really means well. It goes back and forth from being really good friends to being enemies."

Check out everything we've got on "Because I Said So."

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