Original Commentary

Originally, the assistant was going to roll her eyes at Sofia, but it'd be difficult to position the characters to make that possible. So just imagine an eye roll there if you like - Terrence

Modern Commentary
"The vet". She means Dr. Paul. There are other vetrinarians who work there, I'm sure. But as far as Sofia is concerned, there's just the one.

The assistant has been doing this long enough to knows what Sofia means - Terrence