For now, know that you'll gain vet skill while working on patients and can also improve the skill by practicing lab work at the medicine crafting station. You can learn more about the skill levels and what they unlock by visiting that guide. This new feature borrows heavily from the Get to Work Doctor Career, as well as that DLC's Retail feature and Veterinarian Skill which ties in with the business ownership feature, but is not exclusively used for operating a clinic. The Sims 4's ownable vet clinic is available to players who buy the Cats and Dogs Expansion. The Sims 4: Vet Clinics Playing a Veterinarian in the Cats and Dogs Expansion The Sims 4 Cats and Dogs allows players to own and operate a Vet clinic, all while playing as the Veterinarian