Please Help

My mother has just found out that she has Hep C. I am not to sure how this is
transmitted. We live with her and I have a 8 year old son who I am scared
might get this. I know that I might sound nieve but I keep reading different
ways that one could get this Hep C. She doe not know how long she has had it
and my step father was tested and was negitave. I have to know should my
family(sisters, and our children) be tested?

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