The scientist who unwittingly gave him his powers was Professor Egglehead. Due to Streaky, he probably won’t be joining the Legion of Super-Pets.
Current Events
Fuzzy appeared in Superman Family Adventures. Once an ordinary mouse in Lex Luthor‘s labs, having been exposed to radiations emitted by Luthor’s Warsuit he gained a portion of Krypto‘s super-powers and the ability to talk. He’s now a member of the Superman Family.