Innocence lost

Happened to watch the movie Cheeni Kum. It's one of those very artificial movie I have ever seen. Well a different approach is what everyone says and the movie has also won a lot of rave reviews for the subject. But why isn't anyone talking about the way the kid (a cancer patient) is portrayed here. Did we need this character at all?
Guess the trend started wid Kuch Kuch Hota Hai, where Anjali (Rani Mukherjee's daughter) tries to woo Kajol to marry her dad. Similarly here in this movie, there's this little kid, who teaches Big B how to patao Tabu. She must be some 8-10 years old or even less and how on earth does she know about the 'adult world'? Why in the first place are we using kids in movies to promote love between two adults. Can't we leave kids to be themselves?. The child might have simply acted in this movie, but the impact this movie would have had on her cannot be ignored. Her innocence is lost forever!
Why can't we give kids their roles?There are movies like Home Alone and Baby's Day out which have given full scope for children to be natural and showed innocence at its best. And these aren't mediocre movies but had a mass appeal. Even we as adults have enjoyed watching a wonder kid who makes robbers run around the town in Baby's Day out and also in the movie Lost in New York, where a kid who's left behind by his parents at the airport manages to surive at a FIve star hotel with his dad's credit card with his smartness. Such movies are what makes even the child actor and the audience think.
Maybe I'm the only person in this country who's giving a thumbs down to Cheeni Kum. But I guess the reasons are justified. However, there is one good scence which does need a special mention and appreciation in the movie. One most touching scene which is truly realistic is the climax, where Amitabh wishes to have Tabu as his life parner when he tries to bring his hands together in Qutub Minar, while the little kid 'sexy' is fighting for her life back home. Later he realises how selfish he was. This is something that is very close to people's hearts, a scene one can easily relate to. This is because more often than not, we tend to get so selfish, so self-centered that we forget what's the need of the hour. I give full points to the person who has beautifully scripted the scene. This is the only thing that's unforgettable in the movie.