Olga Pataki is Helga G. Pataki's big older sister of the Pataki family of Hey Arnold!.
Olga attended P.S. 118 as a child, and is praised by Helga's current teachers for her achievement. Helga is very jealous of the attention that Olga receives from their parents and of her perfectionism. Olga has good intentions, and tries very much to bond with Helga.
- It is revealed in the episode "Helga on the Couch" that Olga through the years has reacted to her family's problems by being a perfectionist and keeping quiet about the situations at hand.
- Olga attends Bennington College, which is an existing college located in the U.S. state of Vermont.