Roderick Vandenack, or Rod as he asks his friends to call him (or, "The young Dutchman" or "The Barnacle" as they sometimes do), is the son of Mike and Monica Vandenack, owners of the Vandenack Motor Works and Raceway, a specialized car shop and race track located in the hills above Ocean Shores. Rod is of Dutch-American descent; his grandfather moved with his mother and other relatives from Amsterdam during the German occupation in World War II. The Vandenacks landed in New York and eventually found their way to California, where they owned a citrus orchard that produced oranges and lemons on the site that would eventually become the Vandenack Motor Works.
Rod was almost 9 years old when he was first introduced to the fandom, and was in the process of recovering from childhood leukemia. As of today, his condition is "in remission, whatever that means", as he says, though he is still experiencing the sequelae of the disease and the chemotherapy: he is noticeably short for his age and is very thin, even compared to Twister, due in good part to a chronic lack of appetite. On his worst days, he can seem really frail, but those days are less and less frequent, and ever since he met the kids, he's shown a lot of energy and enthusiasm. His optimistic outlook and his friendship with Otto, Reggie, Sam, Twister and the others definitely helped him overcome his condition and even make friends with the terrible Lars Rodriguez.
He is an accomplished Karate student who takes classes at the Crumpackers' dojo, where he sometimes helps his sensei, Lou, to explain the lessons to the other students.
He is also a very skilled mechanic in his own right. He learned from a very early age to fix engines and cars, and in one of the fan stories he appears on actually helped Lars and Twister build their first car, an old Volkswagen Beetle they called "The Yellow Submarine" and which was eventually turned into a successful Baja racer.
Rod is a very competitive racer himself. He can ride BMX bikes, small motorcycles, and even go-carts and small vehicles on his parents' race track. He wants to be a mechanical engineer when he grows up. Otto and the rest of the gang are teaching him how to surf and skateboard, and in return he taught them how to ride a motorcycle and to service properly the "Yellow Submarine".In 2017, Rod discovered his Stand, Staff Flight.