Two things are worth holding through the visiting weeks, and neither one is a limit on candy.

Somebody else is running the house this week

December here fills up with other people's houses. Cousins driving down, a stretch of days at the grandparents' place, an aunt who arrives with a tin and an opinion. Your child will spend a good part of this month eating and sleeping somewhere you are not standing.

The instinct is to arrive with a policy: what he can have, how much, how often. It rarely survives the first afternoon, and it makes you the person who says no at somebody else's table, which turns every sweet thing in the house into a negotiation.

Most of what gets handed to your child this month is not about food anyway. A grandfather with butterscotch in his coat pocket has decided that this is his job, and the point of it is affection rather than the candy. So instead of trying to run the month, pick the two small things that travel with your child into every house.

The first thing to hold is a time, not a limit

Teeth keep track of how often sugar turns up across a day and how long it lingers, rather than the size of any one serving. A slice of pie after dinner behaves differently from that same slice worked on all afternoon. Our guide to kids' diet and teeth is the longer version.

That is useful when relatives are involved. A request about quantity makes the other adult the referee: a number to guard and a child to refuse, which is the opposite of what they came here to do. A request about timing lets them say yes. Right after lunch is perfect is not a refusal. It is a yes with a time attached.

All you are asking is that sweet things come with a meal or a sit down rather than one piece at a time through the day. Another adult can carry that out in a kitchen you are nowhere near, and a four year old can repeat it back to you.

December also hands its sweets over a few at a time rather than in one pile you can sort. That is a separate problem, taken up in our post on the season's steady stream of sweets.

The second thing to hold is a name, not a routine

The brushing failure in a full house is almost never a child refusing. Several adults are awake, the kids went to bed in shifts, and each one assumed somebody closer to the bathroom had it covered. The job had no owner.

So the fix is a name, said out loud. You have got him tonight is a complete instruction, and it lands on a grandfather, an older cousin, your spouse, or the aunt who has been waiting for a job. A vague household expectation becomes one person's task. The American Dental Association puts it at two minutes, twice a day, with fluoride toothpaste. That part only needs one person responsible for it.

The other piece is the toothbrush itself. A brush buried in the shared family kit is one more errand for a busy adult. A brush that belongs to your child, out on the counter of whichever bathroom they are using, gets picked up by the person whose teeth they are. What else goes in the bag is in our holiday travel dental kit guide.

Going away for several days without you makes the name matter more, not less. We will take care of it is warm, and it is not a name.

What is genuinely fine to let go of for a couple of weeks

The two rules are easier to hold if you stop trying to hold everything else. A couple of loose weeks are not what decides how a mouth turns out. The ordinary weeks on either side do most of that work.

• Bedtime. Late is late. What matters is that the brushing happens, not what time it happens.
• The morning brush, on the days a full house gets away from everybody. Twice a day with fluoride toothpaste is still the American Dental Association's standard. A morning brush attached to something that happens anyway, like getting dressed, survives a strange house better than one waiting to be remembered. On the morning it goes missing, the one to guard is the one before sleep.
• Whether it was done well. A seven year old brushing at a sink you cannot see is doing a worse job than you would. It still counts.
• Being the one who does it. If a grandmother wants to stand at the sink and count to two, let her. Her version beats yours, because yours is not on offer.

And the largest item: let go of being right at somebody else's table. Winning that argument costs you more than letting it go.

How to ask a relative without it turning into a standoff

A few things decide whether a request gets honored or becomes the story everybody retells next year.

• Ask early, and privately. A phone call before anybody packs is a favor. The same sentence at the table, with children listening, is a correction.
• Ask one person, not the room. Whoever actually has your child is the one who needs to know. Announcing it to the whole family turns it into a policy.
• Ask for one thing. A list gets nodded at and lost by Thursday. Sweets with meals, and somebody named on the toothbrush at night.
• Ask for something to do, not something to stop. People carry out a yes far better than they guard a no.
• Do not bring us in as the muscle. The dentist said turns a favor into a ruling, and gives the other person something to argue with.

Then there is the relative who thinks you are being precious about all this and says so where everyone can hear. You do not owe that a defense, and defending yourself is what turns it into a scene. We keep it to mealtimes because it is easier than arguing with him at four in the afternoon is true, boring, and impossible to dispute.

If they would like the modern version of any of this, hand them our guide for grandparents rather than explaining it yourself. It was written to be read by the people doing the spoiling, not about them.

The number on the refrigerator beats the rules on the refrigerator

Whoever has your child for a stretch of days needs one thing from you, and it is not a list of rules. It is how to reach somebody if something goes wrong in a mouth.

A few things are not dental questions at all. If a child is having trouble breathing or swallowing, if bleeding will not slow, if there has been a blow to the head, or if a jaw will not line up, that is a 911 call or an emergency room first, before anybody thinks about a dentist. The one dental case where minutes genuinely matter is a permanent tooth knocked all the way out, and the answer there is not to work anything out in a guest bathroom. Call us right then and let the person who picks up sort out with you what it is and what happens next. Everything else is a phone call too, rather than a decision made alone in a kitchen that is not yours.

One number reaches both offices, Monday to Friday, 8 to 5, and a real human answers: (239) 482-2722. Our emergencies page covers what belongs where, and it reads better now than in a panic. If your child is already in the middle of something, braces, an appliance, a tooth somebody has been watching, say so to whoever is keeping them.

Then go and enjoy the people. The relatives are most of the reason the month is worth having, and the two things you are holding are small enough to travel.