I’m as big a sucker as anyone for multiple-handkerchief weepers when they’re done right. At the same time, I tackled Nick Cassevetes’ My Sister’s Keeper with no little trepidation, based in part on how much I had disliked his film of The Notebook — another assault on the tear ducts. And then there was the premise — a little girl (Abigail Breslin) genetically engineered to be the perfect biological match for her leukemia-stricken older sister (Sofia Vassileva), who sues her parents (Cameron Diaz and Jason Patric) for the rights to her own body. In one sense, this is powerful stuff — the moral dilemma of breeding a child for use as a sort of human parts car — but in another, it’s a stacked deck set-up for melodrama of the treacly kind. Those things — and the Hallmark Card trailer — made me wary. The image of Cameron Diaz shaving her head to show her solidarity with her ailing daughter was just too much. And the movie itself is just too much — while simultaneously not being enough. What might have been a pretty heady work quickly gives way to shameless manipulation and a screenplay that’s both sloppy and contrived. Instead of being a thoughtful look at a complicated issue, the movie turns into mush and melodrama of the Lifetime Network “Disease of the Week” variety.