When my boyfriend drives SS10 and SD12 at the end of their visits, I always say bye to them and they say bye back. This is important to me because I think it shows respect and makes me feel like I am important to their visit/it being enjoyable since I do so much for them. When they were younger, boyfriend used to make them give me hugs, but they've aged out of that. I've told him a few times that I expect them to say goodbye and that he can help me by reminding them to.