'Mad Love' taps Brittany Snow as Sarah Chalke's sister

brittany-snow-sarah-chalke.jpgPremiering February 21, CBS's new comedy "Mad Love" features Jason Biggs as Ben, a lawyer, and "Scrubs" star Sarah Chalke as Kate, the girl of his dreams. In a bit of rather inspired casting, the show has tapped "Harry's Law" star Brittany Snow as Chalke's younger sister for one upcoming episode.

Snow shot the guest starring appearance while still working on "Harry's Law," which debuted successfully on Monday. "That was actually really fun, because I felt very busy," she says, speaking with us at a Warner Bros. event on Saturday.

Despite the pressure of playing two characters in one week, Snow tells us she had a great time shooting with the "Mad Love" cast. "Sarah was amazing," she says. "The whole cast was really great. They were so nice and welcoming. I haven't done many guest stars, unfortunately, and it was kind of nerve-wracking to go into a family, and they were just so great."

Expect plenty of sibling hijinks. "They have an overly close relationship," Snow says of the sisters. "It's a really interesting episode... about how overprotective Sarah Chalke's character is towards her little sister. My character kind of wants to break out and just go crazy, so there's definitely a side of my character that she shows to her sister and there's a side that she is actually doing."

"Mad Love" premieres February 21 on CBS.
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