I'm Worried My Sexual Desires Mean Something Is Very Wrong With My Brain

How to Do It is Slate's sex advice column. Send it to Stoya and Rich here. My first crush ever was on my uncle. I've noticed an attraction to two of my cousins. I've never, ever considered acting on these desires or told anyone, but I'm wondering if this is normal. Is my brain missing the evolutionary programming that makes you not want to fuck your family?