Stuck on You finds those fun-loving Farrelly Brothers in a feel-good mood, delivering a tame, kind-hearted comedy that even your grandma could enjoy. That's a big change from the seminal "hair gel" of There's Something About Mary, but the codirecting Farrellys have genuine affection for Bob and Walt (Matt Damon, Greg Kinnear), conjoined twins who are the owners and short-order cooks at a Martha's Vinyard burger joint. When amateur actor Walt decides he wants to make it in Hollywood--where he lucks into a star-making TV role with Cher (who gamely plays herself in this light Hollywood satire)--Bob has no choice but to go along. Separation surgery is risky, so most of Stuck on You milks mild laughs from the brothers' intimate connection, especially when Bob finds love with a pen-pal (Wen Yann Shih) who's initially unaware of Bob's brotherly predicament. Once again, the Farrellys score big points for their progressive acceptance of differences; several minor roles are played by physically or developmentally disabled actors, and it's a consistently commendable aspect of the Farrellys' comedic worldview. Other, more conventional rewards include Eva Mendes (and her ample cleavage) as a bubbly show-biz wannabe, Seymour Cassel as Walt's old-school agent, and Meryl Streep--yes, Meryl Streep--showing good sportsmanship in a glorified cameo. Stuck on You is dispensable comedy, but you can't knock it for good old-fashioned brotherly love. --Jeff Shannon