First, let me say that I am so sorry for your loss. At a young age, they are so vulnerable and can go down very quickly.
I think the goal is to find a reputable breeder that does all the proper testing on these little ones and their parents...Bile acid tests are so important and not all breeders do them. Also, make sure you get at least a 1yr health guarantee against all genetic diseases/defects. Make sure your new pup will have access to food and water at all times and that he/she gets several small meals per day to avoid those hypoglycemic attacks.
My yorkie was 1lb 2 oz at 12 weeks, but our yorkie was very sick when we got him. He had coccidia, hypoglycemia, upper respiratory infection, etc. He almost died, but thank goodness we were able to nurse him back to health. He is now 11lbs and not an ounce overweight. He's just slightly longer and taller
