Caleb

Caleb, a dog of no particular breed, is the only one of the new cadets who was not recruited from a toy store.  On the drive to the Outer Station, Diggity sees him at the base of a garbage dump.  He is taken up and brought along.  There is a reason why Caleb has been lying in a dump, badly damaged and covered with filth; and there’s a reason why Barbara, Gordon, and Diggity end up seeing him there, but you’ll have to find out by reading The New Cadets.