He's a Shih Tzu. His name was Gizmo, but we changed it to Gizzy (because we are oh-so-creative!). My husband calls him and my other Shih Tzu, Daisy "book ends".
They aren't identical- Daisy is 11 years old, and Gizzy is only 2- but they do look a lot alike. They love each other. Started playing right away. Originally we were just going to keep him until he found a new home, but we really like him. He just fit right in with us. My son says he has a familiar face- like we've known him before.
Must have been meant to be.