I think the reason your sister v* when she cam home from the party was because she was most likely drunk. If that is the reason you and your mom will not get sick. Try not to worry about it and over think it. I know it is easier said than done because I am the same way. Last year my roommate at the time went out and came home drunk. The next morning I heard her v* in the bathroom. She did a few times and said how she felt so sick all day. It lasted until about dinner time. She said it was because she was hungover, but I convinced myself it was because she got the sv. I kept cleaning the bathroom after her and got so scared thinking I was going to get it. Long story short, I never got sick, so she was right, it was from drinking and being hungover. I think that is why your sister v*ed on the floor. Try to relax and stay in your room. You will be fine!