Wendy is a Caucasian girl with blue eyes and short black hair. During her days at Happy Harbor High School, she would often wear her Bumblebees uniform, which consists of a black sleeveless shirt with a large yellow H on it, a full sleeve white suit shirt, and a black and yellow striped skirt.
By 2016, she had changed her hairstyle; it was now cropped shorter at the back, and longer at the front.
During the Team's "alien invasion" training scenario, Wendy, along with the rest of the students and faculty hid below the school's underground bunker and watched the Team's speech about how they would win and build from what they've lost, after the Justice League had been killed.
Wendy sat down with Conner to wish him happy birthday, and commented on the fact that his appearance never changes, both biologically and with the S-Shield T-shirt. She reminded him of Megan's surprise parties for him, which she said he only pretended to not like, and he liked them because Megan enjoyed throwing them. She asked him if there would be a party, but he told her that she was the only one who remembered.
Wendy Harris and Marvin White are based on Wendy and Marvin, the two sidekicks from the Super Friends cartoon, along with their pet "Wonder Dog".
In 2006, Wendy and Marvin were introduced into the mainstream DC Comics continuity as twin siblings and supporting cast members of the Teen Titans. While not super-heroes, they worked as tech support and caretakers for the Titans Tower. During a controversial storyline, a demonic Wonder Dog killed Marvin, and left Wendy crippled from the waist down. It was also revealed that Wendy and Marvin are the children of the super-villain computer hacker, "The Calculator". Wendy has since then become a supporting member of Batgirl (Stephanie Brown), where she works as a junior version of Barbara Gordon's computer hacking identity "Oracle". Wendy now uses the codename "Proxy".