I have a crush on my sister's brother in law.?

So here's the story. My sister is married and his name is kevin. Well he has this really cute brother who I have met several times. I have a crush on him. He's 25 and I'm 15. So I know it's nasty. I'm not in love with him like I'm in love with Bradley cooper and Ryan Reynolds. AND my sister is pregnant so she is gonna live in my parents house with me. They have a really big house. So Her in laws and brother in law are gonna stay with us for 2 weeks. So I feel like it's awkward. AND I know this is gonna sound REALLY sick. But I have a very SMALL crush on my cousin. So what should I do about this. Please don't call me sick and nasty. I know that.