If you're having trouble with Travel to Vet, you should probably just travel. Press M on the keyboard, select the world and lot, select your pet as a travel companion (use a filter if necessary), and click the checkmark. (Your pets should show up under Household/Roommates filter and Pets.)
You could also just send your Sim alone, then use the pet's whistle icon (Call Over) to summon the pet.
I have tried just traveling, the same thing happens where the option is not there to go to a different world.
@crinrict Deleting the localthumbcache and opening my game without mods fixed it! I guess I have to go through my mods one by one to see which ones won't break the travel feature.
Thank you for your help!
