Knox is the maternal cousin of Kendra Sorenson and Seth Sorenson, older brother of Tessa, son of Pete and Zola, and grandson of Grandma Larsen and Grandpa Larsen.

He and Seth barely get along, and he tends to brag about the trips and places he goes to with his family, and often makes fun of Seth's breath, and Seth in turn makes fun of Knox's socks.

He unknowingly plays a key role in saving Wyrmroost by retrieving a scepter to reinforce the magical protections of the Black Keep. He did so believing the entire experience was some kind of virtual reality game but was completely ignorant of the magical creatures he'd interacted with, and the dragons he'd inadvertently thwarted.