Ok, background first. My sister (37) and I (35) have a history of fooling around. No details on this aspect, just, it happened. Now I have been going through some things and figuring myself out recently, and realizing that there might be some attraction there on my part. But really just the taboo part. I'm happily married and not looking to mess that up, but at the same time I feel like there is a need in the back of my mind to do more, at least one time. There are circumstances going on currently that have made me realize this, and those circumstances have let to me wondering what to do. She recently became single again, so I know she hasn't done anything in a while, and she was the one to initiate things initially. Advise?