One might be due to asking too much from the game, but non-household animals (Chickens, Cows, Llamas, Mini Goats, and Mini Sheep) will stop belonging to the property owner when they go to another unit for maintenance. You can still collect eggs, but can't do much else.
If your family is the property owner and have their own unit on site, tenants come into the unit, without being invited, and start cooking, using bathroom, computer, getting water and leaving it around, watching TV. You can't ask them to leave because you never invited them in.