Greg's appearance is a mix of Ivan and Chloe. He has his father's eyes and his mother's hair color, freckles and nose. His hair looks very similar to Lincoln Loud's hair. Greg wears a blue shirt, yellow shorts and brown shoes. His voice is very similar to his father when he was younger.
Greg is smart, good-natured, averagely smart, impressionable (like his father) and sometimes overly enthusiastic (like his mother), especially with his best friends, Tommy Turner and David James. Although, he can sometimes be a bit of a prankster, like Bart Simpson from the Simpsons, and cause trouble, especially when one of his wishes goes wrong. In spite of that, Greg is a nice boy. He loves every one of his friends and family, especially his mother, Chloe. Similar to Sidney Poindexter from Danny Phantom, Greg hates seeing his friends and fellow kids being bullied and often tries to stand up for them. Greg sometimes has a mildly bitter rivalry with Otto Buxaplenty, Remy's son.
During April Fool's Day, his pranks backfired which caused his love interest, Mitzie Mulligan to get injured by her leg which brought Greg into deep shame and guilt causing him to leave town until he moved to Venice, Italy staying with hisgrandparents for a while. While doing so, he met up with two marriedgurus who helped teach him into finding his inner peace.