That puppy does look sickly. Here is a link to a six month old pup(only 4 months younger than the one you friend is looing at) he looks alot healthy and notice the size difference. Has the lady send your friend any body pictures of the dog so you can see her whole body not just her sad little face?
I don't think it is common for a Shih Tzu to weigh 3 pd's all that I have see are 7-16 pd's.
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