How to Confirm a Dog's Identity Without Official Papers

https://therescuedogguide.brightpathdigest.com/posts/how-to-confirm-a-dog-s-identity-without-official-papers

Check for unique features like a distinct coat pattern, ear notches, or a microchip implant that your vet can scan. Observe how the dog responds to its name and familiar commands. Look at photos you've taken together over time for consistent markings. Your vet may have old vaccination records with your pet's description. Dog DNA tests are an option too, comparing a cheek swab to stored samples if available.