Thanks for the responses!
The vet did mention low blood sugar and to keep food out all-day until Gizmo is bigger. I forgot she even mentioned low blood sugar - thanks for reminding me!
I worry that he doesn't eat and drink enough, from not being able to be on the floor all-day, but starting today I'm going to keep him off the bed more. Now with unlimited access to his food and water, I really gotta watch for signs of wanting to go potty.
How often do your Yorkies go potty?
Gizmo's breeder had a few big dogs and a cat, so he really wants to go play with Kirby - Kirby just does not want to play with him. I feel bad for Kirby, but the vet said to give him time and he'll get over Gizmo. Gizmo does like to chase our cat!