'Dancing With the Stars': Rachel Griffiths won't follow in Gilles Marini's footsteps

rachel-griffiths-gilles-marini-gi.jpg"Brothers & Sisters" Sarah Walker may need to learn some dance moves fast for the reception if she decides to marry Luc so that he can stay in the country. And seeing as how he's being added as a cast regular, that seems likely.

But Rachel Griffiths (who plays Sarah) will not be following in the "Dancing With the Stars" footsteps of on-screen love Gilles Marini.

"I barely have enough energy with three kids to stand up and get through my lines," Griffiths tells Zap2it. "If you aded a full hour of exercise, I would fall over and die."