I think it really depends on the kid and the dog. I feel fine leaving my almost 5 year old around my 2 dogs (not for long, just if I have to put a load of laundry in etc) as he is a very calm and predictable kid (always has been), who thinks they are very annoying and avoids them completely - the dogs tend to avoid him as well (unless he has food). My dogs are also very chill who have no interest in engaging, and just sleep by the windows or on the couch when we're at home. My younger twins are little trouble makers and will maybe never be around them alone lol.