White, black heart shaped spot in his left ear, black and white tail, silky fur. Black heart in the tip of his nose. Grey eyes. Back legs longer. Big for his age.
Do you mean that his mom has a short tail? Or do you mean that she belongs to one of the breeds with Bobtail in the name, such as American Bobtail, Japanese Bobtail, or Kurilian Bobtail?His mom is a Bobtail.