family affiliations

I was adopted when i was11 and now my adopted sister is dating my blood cousin. They have been talking about getting married and my sister has two kids ( from a previous relationship ) if they get married what does that make them…is my sister now my cousin or is my cousin now my brother?? I am so confused…:smack:

What state are you in?
I believe such laws vary by state, so it’s relevant I think.

your cousin becomes your brother-in-law, though he remains your cousin. You could say your sister is your cousin-in-law, though that isn’t really a term that is used, and when there are multiple relationships, we tend to use just the closest one in practice.

Outside of something like drawing up a will where a phrase like ‘natural born’ might get used it really doesn’t matter. It doesn’t make sense to refer to your sister in a new way. You’ll save a lot of explanations if you just call your cousin your brother-in-law. It’s usually nobody else’s business what these relationships are so use the names you prefer.