I’m in agreement with Robbie on this one. Though it’s true “your very first responsibility is to yourself”, that however may not be your only responsibility. The harsh reality to this is pedophiles like your Uncle will most likely molest others. I am sorry for putting it bluntly but that is reality. Yes some within your family could be disturbed by what they hear if you do talk, but on the other hand what harm could continue if you don’t say something! I believe healing begins by speaking out.
I told about my abuse and honestly it was very difficult to do, but I’m very glad and proud that I did. To this day various family members still have a very tough time believing what happened. However, most people do believe me and are supportive.
Like Robbie said “ITS NOT YOUR FAULT”, it’s your Uncles fault, 100%. You being the child are not responsible for what the adult did.
My suggestion is find the strength to tell about your Uncle. You could be helping your sister and various others. In the end I’m positive you will not regret telling the truth.
Obviously you are a strong person. You are here speaking out.