Set in the apparently godless (but still Christmas lovin') Stone home, The Family Stone opens with the hate-fest that ensues when beloved son Everett (Dermot Mulroney) brings home his new girlfriend, Meredith (Sarah Jessica Parker). Meredith is an uptight businesswoman who wears impractical shoes, so it's no surprise that Everett's laidback, left-leaning family thinks she's a big ol' bitch. Pretty soon Everett thinks so too, after Meredith makes some inadvertently homophobic comments about Everett's gay brother, Thad (Tyrone Giordano). Luckily, brother Ben (Luke Wilson) is on hand with some weed to remind us of an important holiday lesson, and one I learn every year: Christmas is way more fun if you're fucked up. He feeds Meredith enough drugs to loosen up the Virgin Mary, and Meredith finally lets her crunchy hair down.
Meanwhile, Everett hooks up with Meredith's sister (Claire Danes), brother Thad has sign language conversations with his black boyfriend about adopting a baby, and Diane Keaton, as Mommy Stone, stares at the hole where her boob used to be and avoids telling her family that the cancer is back. Needless to say, there's just a bit too much going on here.
The dialogue, though often preachy and/or schlocky, can also be quite funny and engaging, and it's made more so through the efforts of a better-than-average cast. If they'd cut the liberal moralizing a bit, scrapped the cancer subplot, and maybe the pregnant sister (or at least one of the three love stories), this script would've gone down a lot easier. As it stands, it's impossible to suspend disbelief with such an exhaustive assortment of clichés and stereotypes.