Leukemia!!!

One years ago, my mother's cousin was death in blood cancer(leukemia).Which means that the number of white blood cell inside her body are more than the red blood cell...Doctor said, most of the leukemia patient is inherit from their parents...But, at the time we know that no one in our family is having this!!!
Three months ago, my mother's aunt told us that she need to do chemotherapy is because she was checked by a doctor and knew that she is same with my mother's cousin...Leukemia!!!I know that patient of leukemia was very pitiful because got a lot of things cannot eat, need to stay in hospital at lesat one month...Very tired when doing the treatment...
Few days ago, my mother told me that she also the same...I can't believe that my mother was so "lucky"...Is it means i will so "lucky" also???
I can't sleep for this few days...I was very worry...Everyone tell me, the percentage for me to get this was very very very low...But, when everytime i recall back the pitiful of my aunt. i can't stop thinking all the bad things!!!I really scare that i will die after three years just like her...I got many things haven do yet, i cannot cannot cannot cannot cannot let this HAPPEN!!!