Adapted from the chick-lit favorite by Jennifer Weiner, this seriocomic sob story of wildly different sisters and their estranged grandmother is a throwback to old-fashioned melodramas about the family ties that bind. Once upon a time, Curtis Hanson's sure-handed storytelling and the cast's rock-solid performances would have been taken for granted. But in an era when mainstream American filmmakers seem to have lost the knack for making movies about friendship and family that are neither slapstick nor self-conscious pastiche, its matter-of-fact competence is a minor miracle. Smart, successful, responsible, frumpy Rose Feller (Toni Collette, who gained some 25 lbs. for the role), a Philadelphia lawyer, has been looking after her gorgeous, irresponsible, barely literate younger sister, Maggie (Cameron Diaz), since they were motherless girls. Rose bails Maggie out of drunken scrapes, props her up when she loses yet another dead-end job and takes her in when their status-conscious stepmother (Candice Azzara) throws her out on the street. After Maggie humiliates herself at her 10th high-school reunion by passing out in a rest room during a sloppy, alcohol-fueled hookup, Rose lets her move in yet again, on the condition that Maggie shape up and get a job. Maggie doesn't, of course; she leaves the apartment a frat-house mess, borrows Rose's car and gets it booted, raids her shoe closet and, worst of all, sleeps with Rose's new boyfriend — the first man her workaholic sister has dated in ages. Tearful and at the end of her tether, Rose throws Maggie out and takes a good, hard look at her own life. She quits her high-pressure, unrewarding job and becomes a dog walker; starts dating former coworker Simon (Mark Feuerstein) — who thinks she's beautiful — and even loses some weight, not by dieting but by running after dogs and laying off the midnight tubs of double-depression crunch ice cream. Maggie, meanwhile, makes her way to Florida, where she moves in with (or, more correctly, moves in on) Ella (Shirley MacLaine), the maternal grandmother who disappeared from Rose's and Maggie's lives after their mother died in a single-car accident. By the time all the skeletons are out of the family closets and the raveled relationships knit up, the sisters are reconciled and forgiveness has rained over all concerned like wedding-procession rice. And it's wonderfully satisfying: Collette, MacLaine and Diaz are exceptional, and the mix of humor and heartbreak is perfectly calibrated.