Where the pet came from, in writing
Start the folder with origin paperwork: the adoption agreement from a rescue, the breeder's birth and parentage record, or a signed note from a private rehoming. This establishes age — or the best honest estimate of it — sex, and how long you have had the animal, all of which vets, insurers, and boarders ask about. Add dated photographs showing colouring, markings, and any distinguishing features such as a torn ear tip or an unusual coat pattern. For animals as lookalike as guinea pigs in the same colour, good photos are often the most convincing identification you have.
Keep proof of purchase or the adoption fee receipt in the same section. It rarely matters, until the day ownership is questioned or an insurer asks, and then it matters completely.
Health records: the working core of the folder
For rabbits, file the vaccination card showing myxomatosis and viral haemorrhagic disease dates, plus neutering confirmation. For both rabbits and guinea pigs, keep vet visit notes and invoices in date order — invoices double as a treatment timeline, listing what was examined, what was found, and what was advised, even when no separate clinical summary was given. If your pet has ever had dental treatment, gut stasis, skin treatment, or surgery, those records deserve a marker or divider: they are the pages a new vet will want first in an emergency.
Add your own weight log. A dated list of monthly weights, jotted on one sheet, is genuine health evidence for prey animals who hide illness well, and it belongs with the clinical papers rather than in a kitchen notebook that gets thrown away. Note appetite or behaviour changes alongside vet visits in the same running record, briefly and factually.
Identity, insurance, and money papers
Keep the microchip certificate or a note of the chip number and registry name, with the date you last checked the contact details were current. Guinea pigs are less often chipped than rabbits, which makes their photo record and origin papers carry more weight. File insurance policy documents here too — policy number, renewal date, excess, and the claims phone number — or, if you self-fund vet care, a simple note of the vet practice's payment terms and your emergency plan.
Also keep contact details in this section: your usual vet, the out-of-hours provider your practice uses, and an emergency contact who knows the animals. In a crisis, whoever picks up the folder — a partner, a sitter, a family member — should find those numbers on the first pages, not buried under invoices.
Care notes that keep the folder alive
The last section is the living one: current diet in exact terms, housing and cleaning routine, handling preferences, bonded companion details, and any quirks a stand-in carer needs. Update it whenever something changes — a new pellet, a changed green, a companion lost or gained — and date each version so an old sheet is never mistaken for the current one.
Review the whole folder twice a year. Check that vaccinations are in date, chip details still point to you, insurance has renewed as expected, and the care notes describe the animal you have now rather than the one you had a year ago. KinsLe's Pet Passport brings those same records together in one portable packet — health history, identity details, and care essentials — so the folder's contents can travel to a vet, boarder, or sitter without being photocopied page by page.