My sister-in-law is Homo, Should I inform my brother?

I found out last  weekend that my brother’s wife and mother of his two children is just a lesbian and I don’t know how to proceed about this information. Should I tell my brother? She had s3x with another lesbian at a friend’s house in Parkview  and I don’t know how to proceed with this information. I’ve suspected for quite a long time but my suspicion was just confirmed on Saturday. I don’t know what will happen if I tell my brother she can’t continue living a dual life, going to church every Sunday and giving advice like Mother Teresa when she lives a dirty, disgusting life. Check it out again and see!