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Definitely NOT the runt!
I am the proud 'grandmother' to 5 four week old pups. I have both mum & dad, and this is the first (& last!) litter. I understand that the parentage of mum & dad come out in the pups, but, whilst all five are similar looking and defo' JR's, one of them is half the size again of the others (all same size at birth). Is this a problem, or is he just a 'piggy'?