The group record is the paperwork that matters most
Fancy mice are kept in groups, and their paperwork is usually a group record rather than individual files, so a house move is the moment to rebuild that record properly. Start by updating the address held by your veterinary practice for the colony, then rewrite the census itself: every mouse's name, sex, coat colour and markings, approximate age, and any ongoing health note. Mouse groups change constantly through births, adoptions, and deaths, and the list a vet or sitter inherits after a move is very often several mice out of date — which is how the wrong animal gets described on a phone call about a sick mouse nobody can identify.
Vet registration in the new area
If the move takes the mice to a new practice, choose one that sees small rodents routinely and transfer whatever history exists, flagging the entries with long shadows: respiratory flare-ups, tumours removed or monitored, and any mouse on a watch-and-wait note. Fancy mice are prone to respiratory problems, and the new house itself belongs in the record — note whether the cage now sits in a room with scented candles, aerosol cleaning, a wood burner, or dusty hay storage, because a new vet investigating sneezing mice will ask about exactly those triggers and the answer is easier to give accurately while the move is fresh.
Sitter and emergency sheets with new geography
Rewrite the sitter care sheet and emergency plan for the new address rather than crossing out the old one. The backup person should be someone near the new home, the out-of-hours clinic may be a different practice from the old area's, and the practical directions — which room the cage is in, where the food and spare bedding live, which carrier the mice travel in — all change with the house. For a mouse group, the emergency sheet should also say how many mice a carer should count, since a quick visual check against a stated number is how an escape or an unnoticed death comes to light early.
Origin and breeding records, if you keep them
If your fancy mice came from a breeder or you breed occasionally yourself, update your address with the breeder and refresh the litter records filed with the group paperwork. Fancy mouse lines are tracked by variety and ancestry among breeders, and a stale address breaks the chain if a genetic question — a recurring tumour pattern in a line, for instance — ever needs tracing. Even for purely pet mice, keep the acquisition notes with the new address sheet: where each mouse came from and roughly when is the first thing a vet asks when a whole group shows the same symptom.
One updated version for everyone who helps
Mouse care in many households is shared — a partner feeds in the week, a parent mouse-sits during holidays — and a move multiplies the chances those people are holding different versions of the group's details. Retire the old sheets physically rather than leaving them in the drawer under the new ones. Putting the refreshed census, address, and vet details in KinsLe through Family Sharing gives every person who helps with your fancy mice the same shared profile to work from, so the update is made once and seen by all of them.