2 This small working dog: At just just 2 1/2 pounds, Lucy holds the record for world’s smallest working dog. But don’t be fooled by her vest that says “therapy dog.” She actually has the strength of a horse and is rather good at pulling sleighs. Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17