BRINGING Jodi Picoult’s challenging novel to the big screen was always going to be a tough task, but director Nick Cassavetes just about pulls it off.

My Sister’s Keeper is a moral dilemma for the modern age. Sara Fitzgerald (Cameron Diaz) and her husband Brian (Jason Patric) decide to genetically engineer a sibling to be a blood and bone-marrow donor for their sick daughter Kate (Sofia Vassilieva).

After enduring years of painful operations to save her sister, who next needs a kidney transplant, the 11-year-old Anna (Abigail Breslin) takes her parents to court to sue for the rights to her own body.

Kate was diagnosed with leukaemia as a toddler, and her lawyer mum, Sara, dropped everything to look after her, never sure when the next nose-bleed might result in a lengthy hospital stint. She’s clearly a supermum, who almost treats her daughter’s illness as though it’s a courtroom battle to be won.

But Sara’s intense focus on getting Kate better, by any means, takes its toll on the rest of the family, especially when she faces the real lawsuit brought by hotshot lawyer Campbell Alexander (Alec Baldwin).

The complex web of relations between each family member – from the forgotten son Jesse (Evan Ellingson) to the impenetrable bond between Anna and Kate – is handled sensitively, through a series of voice- overs from each actor.

This works, in the main, to give the viewer an insight into each character’s thoughts on the situation, but occasionally these sequences, using music and sometimes grainy flashback shots to set the mood, detract from the action.

Kate’s voice is one of the last to be introduced, but is perhaps the most poignant, as she reveals: "I don’t mind my disease killing me, but it’s killing my family, too." This is the crux of the film.