Wendy Harris, Marvin White and Wonder Dog are fictional characters from the 1973 American animated TV series Super Friends, based on the famous superheroes published by DC Comics. The series featured a lineup of DC's most popular characters, including Superman, Batman and Wonder Woman, but Hanna-Barbera, the show's producers, wanted to include young sidekick characters that the children in the audience could identify with. This led to the creation of Wendy, Marvin and their hero pet Wonder Dog, who appeared alongside their more famous friends. Because of the success of the Super Friends cartoon, a Super Friends comic book was also created, in which the trio made their first comics appearance.

Super Friends is a 1973 animated series produced by Hanna-Barbera and National Periodical Publications. It is based on the Justice League comic books, and is the first incarnation of the Super Friends series.