Because every cowboy needs a horse, this is Tildy: Henry's lambeosaur mount.

(Keep in mind that Henry isn't actually a cowboy. That being said, Tildy isn't a horse.)

She's a stolid gal. Like her owner, Tildy's seen everything and is smart enough not to go looking for trouble before it comes looking for her. Henry will call her by her full name (Matilda) when he's feeling especially nervous, or wistful.

Dinosaur adopt by  Tanuklear