In Sonic XEdit
Chris lives with his grandfather Chuck Thorndyke (who is a scientist), his bodyguard and butler Mr. Tanaka, and his maid named Ella (Sonic). He lives in a large mansion due to his parents' success in their individual fields of work. Chris' father Nelson Thorndyke runs an electrical appliances company, while Chris' mother Linsey Thorndyke is a famous actress. As a child, Chris rarely saw his parents, which made him become very lonely to the point where he feels threatened by abandonment when Sonic and the rest of Chris' friends return to their world, even though it wasn't their fault that they had to leave. His uncle, known as Sam Speed, is the head of a police car-chase team, known as the Speed Team, drives a Formula One race car and has some sort of rivalry with Sonic. Chris' elementary school teacher is Mr. Stewart, who turns out to be a spy working for the government later in the show.
At the end of the 2nd season and during the 3rd season, 6 years has passed and Chris becomes 18 years old. Early in the third season, he uses a portal to travel to Sonic's home in the show. After this point in this series, Chris is still in his pre-teen design and still speaks and thinks in his younger voice since the passage of time is different in Sonic's dimension. Yet he has the memories of the past 6 years of his life prior to traveling to Sonic's world. However, he has gained new skills during the 6 years in between the show. Chris no longer takes the back seat in the X-Tornado; instead, he is shown as flying it capably, which his younger self would never have done. Chris also comments in one episode that he is a black belt in karate. Additionally, he has also shown to have become a quite capable engineer, enough to impress the super-smart Tails. He invents different gadgets and devices like Sonic's Hovershoes, a hoverboard, and a new, better Chaos Emerald scanner for the Blue Typhoon. He is also seen in a few episodes using Flash Bombs as a distraction and he also uses a laser gun as a weapon.
Story of Joining Sora's TeamEdit
When Dr. Eggman manged to get Chris back home, he was turned back into an adult and his clothes changed but in the wrong location in his world. Soone when there was a flash in the sky at night, Chris met Stitch, Jake the Dog, and Bugs Bunny fall from the sky(which was actually their ship), and they sought help from Chris to reunite them with the team. When Chris managed to get a ride back home, he was ambushed by Heartless, and Nobodies, who were lead by Xemnas. When their fight was short, thay lost but were saved by Riku, Gossamer, and Ice King who were with Helen. After Chris and Helen caught up, they met Sora, Slushy, Daffy Duck, and Marceline who were with Danny that they recieved a message from Kairi saying the Keyhole was located in the city were she , Finn the Human, Frances, Snafu, Tweety and Gunter. When everyone met up, they engaged in combat against Pete, and The Trix when the keyhole was at the portal Chris made. Soon the showdown lasted about 56 sec. after Chris brought out one of his inventions and blasted Pete and The Trix to knock them out. When Sora used the Keyblade to open the pathway, Chris, Danny, Francise, and Helen decide to join to help save other worlds from darkness and hoping to see Sonic again, and they did, as they already were members of the team.