You can now require that clients choose their pet's vet when they add a new pet through Client Portal.

In Live Access, click on Online Reservations, OLR Settings.  Click on the General tab.

Check the box to "Require vet information to add pet".  Be sure to hit Save Settings.

Now when a client adds a pet, it will require that they choose a vet.  They will only be able to choose a vet that's already in your database.