Cat - severe weight loss
* Species: cat
* Age: 12-ish
* Sex/Neuter status: neutered
* Breed: ragdoll
* Body weight: probably around 7lbs now
* History: unknown
* Clinical signs: unknown
* Duration: unknown
* Your general location: michigan
Hello. I live with my sister and her husband. They have a ragdoll cat that lost almost 5lbs in a few months. In Jan 2025 he was 12.4lbs. I think he started losing weight around July/August. By December 2025 he was down to 8.6 lbs. He used to be big and fluffy and now he is rail thin. He seems to eat fine but nothing sticks. They have had him to the vet and I am linking their findings from Jan 2026. I have had several arguments with them to take him for more testing and the latest resulted in me being told "he's not your cat". I've included results from google artif from my effort to try and figure this out myself. I am not asking for a diagnosis but rather possibilities on what could be wrong and what to check for if I can sneak him to the vet myself. Link below with pics of recent medical history.