Tell Him that God Doesn't Hate Him

Hi, This one I am sure you will be able to help with. My son suffers with Crohns disease, he was diagnosed at six, although he has had it since just a year old. He is now 12. We have been to the hospital today because he hasnt been feeling so weel recently and it looks like the disease may have spread. There have been so many times I have been so angry, why my child? what did he do wrong? He is now reaching adolesance and is feeling the same thing, I dont know how to answer him when he asks me why he has this incurable disease, and I cannot blame him for turning his back on Christ because i did do the same thing, although i found my way back. My question is, how do I explain that God doesnt hate him, and God isnt punishing him by giving him this illness? And any ideas on what answer I can give when he asks me why?