Your child has friends coming over. Your 10 month old dog, 30kg of enthusiasm, meets them at the door and puts both front feet on a 7 year old.
This is a normal adolescent greeting and it is still not acceptable here. A visiting child is smaller than the dog, faster to squeal, and not yours.
The part that is different from adult guests
Another parent has handed you their child for 2 hours. They have not consented to any risk from your dog, and they were not asked.
That changes the standard. With adult guests you can run a greeting and accept a mistake. With visiting children you plan so that the mistake has nowhere to happen.
Running children are also the hardest thing in the house for an adolescent dog to ignore. Speed, noise and height are exactly the combination that tips a young dog over.
Before they arrive
Decide now where your dog will be: a bedroom, a crate they already like, or behind a gate in the kitchen. Decide it before the doorbell, not during.
Walk your dog first. 20 minutes of sniffing, well before the visit, not a run 5 minutes beforehand.
Set the room up: a filled and frozen toy, a chew, water, and their own bed. The separated space is where the good things are.
Put a house lead on the harness if your dog will be out at all, so you can move them without grabbing.
Pick up the things worth guarding and the things worth stealing: chews, bones, the children's snacks, coats and shoes.
The arrival, in order
Put your dog away before you open the front door. The doorway is the worst place in the house for this.
Let the children get in, get their shoes off, and get settled somewhere. The dog does not need to be part of the arrival at all.
Say the rules out loud to the children. We do not go in that room, and the dog comes to you rather than you going to the dog.
If you bring your dog out, bring them on the lead, into a group that is sitting still. Pay 4 feet on the floor with food at your knee.
Give it 3 minutes, then put your dog back with something to chew, while it is still going well.
Ending a good greeting early is the whole skill. Every visit that finishes before your dog gets over-excited is a visit that taught them something.
The rule that never bends
Visiting children and an adolescent dog are never left in a room together without an adult watching. Not for a minute, not while you answer the door, not while the game seems fine.
Supervision means watching the dog, not being in the building. If you cannot watch, your dog is behind a door, and that is not a failure of hospitality.
Separate for high-speed play, garden chase games, trampolines, scooters and anything with squealing.
Separate for food: children eating on the floor, birthday cake, snacks in laps.
Separate when the visit is winding down and everyone is tired. That is when the supervision usually slips.
Tell the visiting parent, plainly, that you have a young dog and how you manage it. Some children are frightened of dogs and their parents will thank you.
What to practise between visits
Behaviour change is built from management plus reinforcement. The management is above, and the reinforcement is these short sessions with no visitors in the house.
Pay 4 feet on the floor 10 times a day with your own family, especially when your dog approaches someone who is standing still.
Practise going to the separated room and staying there, in short paid sets with the door shut and you nearby. Relaxation is a behaviour trained in its own right.
Rehearse the doorbell with nobody there: bell, dog goes to the room, chew appears, door opens onto nothing.
Recruit 1 older, calm child you know well for a 5 minute paid greeting, and treat that as the training, not a party of 6.
Reward-based methods are what is recommended for training and behaviour change, and they are the only methods used here. Nothing about a house full of children changes that.
Safety note
Get help now if your dog has growled at, snapped at, mouthed hard at or bitten any child. The same applies if they stiffen and stare at children. Separate your dog from all children completely, book a veterinary examination, and speak to a qualified behaviour professional. Pain frequently presents as a change in behaviour rather than as obvious lameness, and sudden behaviour change warrants an examination. Do not manage a bite risk around visiting children on your own.
Today's version, in one line: pick your dog's room, freeze a stuffed toy for it tonight, and use it before the door opens.