My little "teacup" was the runt; she is just over 2lbs at 5 months old.
She was still quite a bit less than a lb at 8 weeks according to the breeder, so according to triple-rule thingie she won't be much more than 3lbs, if she makes it to that.
I had to wait until she was at least 4 months to pick her up, though...
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