What would you sacrifice to save your dying child? Your wealth? Your family? Your friends? How about one of your other children?

For most people this would be something of a moral dilemma, but not for Sara Fitzgerald who happily offers her youngest child, Anna, up as spare parts in order to save the life of Kate, her older cancer-stricken daughter.

You see it's OK because Anna was genetically engineered specifically to help out her sister. A kidney here, some bone marrow there. You need an ear? That's cool, Anna has a spare. It's all really quite fine.

Or is it? Is it really fine to use a child in this way?

Unfortunately, we never get to find out as Nick Cassavetes' heavy-handed adaptation of Jodi Picoult's best-seller provides even less answers than its source material.

When 'My Sister's Keeper' became the staple of book clubs the world over back in 2004 it did in fact receive some criticism even in the wake of its roaring success. Critics claimed that Picoult came up with an original and controversial topic — the morality of using one child to save another — and then never actually bothered to address the issue in any depth. They bemoaned her copout ending which effectively renders the entire story meaningless. And she was criticized for writing, frankly, an over-inflated story too smug and sure of its own importance.

Unfortunately, all these complaints — and a few more — can be leveled at the film. Meaningless flashbacks, saccharine voiceovers and emotional angst are squished together clumsily in an obvious attempt to get the tears flowing and keep them that way. Yet they hardly make up for lack of real debate, the lack of really investigating the questions that are presented.

That said, 'My Sister's Keeper' does have its moments. Sofia Vassilieva as the dying Kate is particularly moving. One can't help but sympathise with her plight as the forces around her spiral out of her control and she's effectively forgotten in the raging emotional battleground that her family has become. Alec Baldwin, as lawyer Campbell Alexander, is also a treat while Abigail Breslin as Anna adds a much-needed lightness to the film.

And then, of course, there's Cameron Diaz in the role of Sara Fitzgerald. While Diaz has certainly upped her game for this difficult role, there's little compassion to be had for an incessantly whining character unable to take responsibility for all her children.

Her ridiculous courtroom arguments in favour of harvesting her child's organs — "She's my daughter, I can do with her what I like" — leave one feeling cold, a little put out, even cheated.

'My Sister's Keeper' is an emotional rollercoaster, have no doubts. You'll be saddened, angered, even enraged but ultimately left disappointed.