When a parent arrives normally all the kids rush to the door area anyways and then it is as simple as me answering the door and then allowing only the correct child to come to the foyer area - have a gate. I stand there and chat a bit about the day while child gets dressed for going home. I step in if child acts up as I want it to go smoothly and quickly and all of us parent included are tired and just don't feel like dealing with it. I speak to child reminding them that when they are at my house they do as they are told basically. Most often a parent is grateful for the help. Those that aren't well too bad it is my home and your kid can't act like that here. My house my job to remind child of the rules not the parent.