When we first got our puppy Izzy, we bought her a small Kong ducky. This has been her favorite toy. She holds it in her mouth and squeaks it. She will then throw it up and chase it. She plays all kind of games with herself with the duck. I have bought several extras because she has taken the duck outside and it got rained on and ended up rotting. Any of the small Kong toys are great .. we have the bear, beaver and frog. She loves them all.
This little squeaker toy has now become my Cairn Terrier's favorite. He plays with it every day and keeps it close to him so he doesn't lose it. It is just the right size for him and he is never too far from his ducky. :-)