Has My Son Gotten Over The Worst Part Of His Health Issues?

My 22 month old, Joshua, had a liver transplant 9/10/07. His father donated. Josh has had some ups & downs since then. He is doing well at the moment, but as a mom I constantly worry. I am scared that we won't have him for long. I keep having dreams that I am terminally ill and I'm scared that means something like I'm going to die because Josh is going to and he needs a mommy in heaven to take care of him. Someone please give me some reassurance. I love Josh so much.