The Boston Terrier comes to mind as one that is small but not
too small, and FULL of energy. But there are SO many breeds... you might want to take the breed selector quiz on the DogBreedInfo site -- that will at least give you a lot of ideas.
Whatever you decide on, it would be better to wait until your pup is a bit older before adding another puppy to the mix. The general recommendation is to wait until the first puppy is 2 years old before getting another one. That way the older dog can be a role model for the new puppy, since the older one has already had 2 years of training and bonding-time with the owner. Plus, at 7 months old your guy is just hitting his "terrible teen" stage -- probably not the best time to be adding to the family
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Zoë
Creek - Fawn Female, born 03/27/2001
Caney - White Female, born 03/26/2007
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