visitors over, some of them are not fans of our dogs (I can sympathize with them - our dogs, while not dangerous, are objectively terrible and I look forward to their eventual, natural deaths). When those people come over, we shut the dogs away for the entirety of their visit. It is not an unreasonable request, especially if you feel like it's a safety issue. Just say "If you don't mind, I'm not comfortable with my kids around the dog. Can you put him away while we're over?"

If they object they are being lame.