Hi Nancy. It does happen that people get counted twice, although I don't think it happens all that often. I had some ancestors where an entire family was enumerated twice, without moving, apparently because two different census takers covered the same rural road a couple of weeks apart. I had a couple of other cases where people were counted twice because they happened to be visiting relatives when the census taker came down the road. I never saw a whole family enumerated twice in different years, so you probably have a rarity there. But records are records, all created by fallible humans, so you just deal with what you can find.