I feel like a creep

I never told anyone, but I know of at least two people in my family who have engaged in incest in the past. Unfortunately, I do not know for certain if they continued doing it over the years, or if my cousin has been able to give a try. <br>My sister recently learned that our aunt and uncle were engaged in a secret relationship while our grandparents were still alive. <br><br>This aunt and uncle have a teenage daughter, and my sister claims that she has seen her cousin locking the door to the room she is sharing with her aunt while she is staying in our house. Like, is she open with her parents about being in a relationship with a member of our side of our family? Does she have the same feelings as I do? <br><br>I don't know what to do. My dad says I should be patient, and my sister has told me again that I shouldn't say anything about it to any of my other siblings.