Hello! I too have a tiny yorkie Rasta's a gigantic 1.7 lbs at 3 months
. He too has the alpha mentality and tries to boss around our English Bulldog who's a total pushover lol. I would say the only things I really worry about with him being so small is getting stepped on(he is pretty good about moving out of people's way tho) hypoglycemia...we haven't had a scare yet though. Other than that I would say no other worries that a "normal sized" yorkie's parent has. Rasta usually lets me know when he has to go potty by barking...we tried potty pads for a few days but he seems to like doing his business outside(following his bulldog sister's example I guess). He does still have an accident about once a day and I've found white vinegar works very well to stop repeat marking as well as getting rid of stain/smell in that area.