About me and my life in the past few months

I'm a single mom of 2 kids and both have medical problems. I deal with seeing them everyday . My oldest daughter is 4 1/2 and she has seizures. She has had them since she was 1 and 1/2 she is on med and hasnt had one since easter sunday. She only has them at night while she is sleeping. The day after she is so tired and worn out that it is sad. She can't even play with her sister. The doc says if she still has them when shes 10 she will have them forever. If she has them forever what is not going to be able to do? They don't really know what causes her to have them. It is very scary. My other is 3 and 1/2 she was just diagnosed with kawasaki disease. When they first told me I was trying to figure out how my daughter had a motorcycle disease. Then I found out all the different outcomes of it. I about died. The thoughts that ran through my head were crazy. How can I tell my doughter that her sister might not come home. How can I handle the lose of a child just a baby. She is so innocent she don't eserve to suffer like this and she is. We caught it at only 7 days so it was early enough to stop the heart damage but there is so much more that can happen. Now she complains alot of leg/hip pain and i'm scared to death that she might get authritus from this. I picture her having trouble walking and doing normal things that kids do. All I ever wanted for my kids were to have normal lives doing normal things and having fun. And I don't know if they will ever get to.