Tommy was the oldest son of Hidaka Reiji, the leader of a pack.
Shin Gaiden 1 - Chōmon no TabiEdit
When his father left to fight against Akakabuto, Tommy and his brothers stayed to watch over the pack and the territory.
Unfortunately, the nasty dog called Muramasa took over the pack and the leadership by using their mother as hostage. Muramasa started to rule with harsh and cruel way.
Unfortunately, Tommy and Sabu only managed to reach the neighbor territory as they were quickly found and killed by Muramasa's minions. Tommy's body was found by Zack and his pack members.
Later, Tommy is buried by Shin who mourns his death and feels guilty because he didn't try to help his brothers when he had a chance.
See more pictures in Tommy (SG)/Gallery.