Well my doggies went and got their vaccinations. I asked, vet was in a really good mood and he said similar to what you'd said. The booster ones can go longer as long as the first one didn't expire before it was done with the booster. Anyway, was pleasantly suprised on doggies weights, Chloe was 4.2lbs, Bella was 6.4 and Taylor was 7.2lbs.
Now to get their city tags and we're all set to go. Yay!