Kong also makes a ball that has handles molded into the shape of the ball, and that might make it easier for a small dog to hold onto, as he/she could get just the handle in his/her mouth and carry it around that way. My dog is around twenty-five pounds and is a seriously aggressive chewer, and he's had one of those balls for over a year, and not only is it still in one piece--it actually still squeaks. He did manage to break the squeaker in a second one, but it also is still entirely in one piece.
They make that style of ball in three sizes too. I've gone with the mid-size one, but your pup might make use of the smallest size. They do have a small tennis ball inside the larger ball (the ball's translucent, so you can see the smaller ball inside the larger ball), which some might find worrisome, but my dog hasn't been able to come close to puncturing the larger ball and he once cracked a puppy Kong and peeled it like an apple to get to the treat in the end of it.
I think the mid-size one runs around $12, but I think the investment was worth it because he was unable to destroy it and still enjoys playing with it. He actually has a smaller Kong ball that I didn't think would be as durable--around the size of a tennis ball--and he plays with that less, but it still squeaks too. He will sometimes just lie there with it in his mouth, squeaking it over and over again (which is why he's allowed to play with it less--if he played with it more, I'd be the one breaking its squeaker).
