You are having the same problem that I have with my yorkie,Lady.She is at 2lbīs at amost 17 months old and we also have had her on a high calorie suppliment for months now.I must warn you that the tiny yorkies like the ones we have,DONT grow out of hypoglycemia due to their size,which is why its wise to leave food out 24/7 and make sure they eat a few times during the day.You arent over feeding your baby because if they arent hungry they dont eat,so dont worry about that.We feed Lady alot,she has puppy kibble out 24/7 and has her high calorie canned food 3 times a day.Her weight drops every time we have taken her off of the high calorie food,so my vet has decided that we should give it to her permanently.This last time her weight dropped to 1lb 11 ounces.She is very fragile and quite thin so there is no harm in her eating the high calorie food at all.Also,your vet may recomend that you never take your baby off of the puppy food either because is it richer than adult food,this is also my case.Because your baby is small,it doesnt mean that she will be sick

Lady is tiny but she is full of life and has never had any problems at all

Our vet wants to keep her weight at 2lbīs+ because he thinks its better than weighing under 2lbīs...your baby can still put weight

Lady weighed quite a bit under 2lbīs until she was about a year old,then we started her on her high calrie food and her weight went up to 2lbīs so your baby still has a few god months of growing time
If your baby still has her teeth baby teeth at 7months old,you may want to ask your vet about having them pulled.Lady had to have almost all of her baby teeth pulled when she was spayed because the smaller yorkies CAN have problems losing their own teeth and sometimes they need help.I hope Iv helped you out

Dont worry too much about your baby being small,it DOESNT have to be a problem at all,infact,apart from their size,they dont have to be any different than one of the bigger yorkies (I also have a 1 year old yorkie who is at 7lbīs).I would leave food out or your baby 24/7,make sure she drinks and eats regularly and give her lots of lovin

Im sure sheīll be fine