Alison Arngrim and Melissa Gilbert were on-screen rivals in the hit television show Little House on the Prairie. But their connection was very different behind closed doors. At the show’s 50th Anniversary Cast Reunion and Festival, Arngrim—who played schoolyard bully Nellie Oleson—talked candidly about her special relationship with Gilbert, who played Laura Ingalls Wilder, in an exclusive interview with PEOPLE.

When the cameras stopped, Arngrim, now 62, and Gilbert, now 59, would spend time together like sisters, she remembers with fondness. Together, they also coordinated their battle scenes, beginning in 1973, the year they first started working on the show. In a lighthearted way, Arngrim calls their friendship “completely bonkers.”
When show viewers see a picture of Arngrim and Gilbert grinning together behind the scenes during a Christmas episode where their characters clashed, they frequently express astonishment. “It’s little Nellie and Laura, but you’re smiling,” people would say. That episode doesn’t feature any smiles between the two of you. “I’m like, ‘This was us for real,'” says Arngrim.

The audience wasn’t always able to distinguish fact from fiction, however Arngrim and Gilbert were able to do so. Viewers had a hard time telling Nellie Oleson’s bully character apart from the actress since she had become such an iconic figure. Arngrim can clearly remember times when individuals showed their contempt for her persona—one even threw an orange soda cup in her face when she was participating in a Christmas procession.
Fans’ unfavorable responses notwithstanding, Arngrim has come to accept her role as a bully. In a live one-woman performance titled “Confessions of a Prairie Bitch,” she also discussed the experiences she had while filming the program. She finds it fascinating how people react so emotionally to her that they start to believe that her character is real.

One thing that serves as a reminder that on-screen personas can be misleading is the friendship between Melissa Gilbert and Alison Arngrim on Little House on the Prairie. Actors who play antagonists on screen can occasionally be the closest of friends off.