We've already seen Rachel McAdams in a bridesmaid dress onscreen (remember "Wedding Crashers"?) — but this weekend, the actress got to wear one in real life.
McAdams, 36, donned a lovely blue halter frock for the nuptials of her sister Kayleen, a Los Angeles-based makeup artist. The ceremony took place at Port Cunnington Lodge in Muskoka, Canada.
The "Notebook" star isn't the only celebrity bridesmaid we've spotted. Here are a few other stars who've supported a close friend or family member on her big day.
Eva Longoria
The "Desperate Housewives" actress sported a strapless tulle gown for the wedding of her friend Alina Peralta in Cordoba, Spain, earlier this month.
Rihanna
The singer clearly had a blast serving as a bridesmaid for her friend and assistant Jennifer Morales' wedding in Hawaii last month.
Sarah Jessica Parker
The "Sex and the City" star stunned in a fuchsia gown when her former assistant Melinda Relyea tied the knot last summer.
Jessica Simpson
Simpson shared a sweet photo of herself as a bridesmaid and daughter Maxwell as a flower girl for sister Ashlee's wedding last September. "I am madly in love with this moment!" she wrote.