THE TWINS BEHIND CARRIE INGALLS WERE FINALLY GIVEN THEIR BIG MOMENT ON LITTLE HOUSE ON THE PRAIRIE — BUT BEHIND THE CAMERAS, THE EXPERIENCE WAS FAR FROM WHAT THEY EXPECTED. Lindsay and Sidney Greenbush had spent years sharing the role of little Carrie before an unusual episode finally placed both sisters in the spotlight. What should have been an exciting career milestone came with unexpected pressure for the young actresses. Their mother was away, their father was on set, and the twins faced challenges they hadn’t encountered before. Decades later, their memories reveal a surprisingly personal side of the episode that remains controversial.

The Greenbush twins played Carrie Ingalls on NBC’s Little House on the Prairie, and they understand why this Carrie-centric episode is so controversial with fans.

Sidney and Lindsay Greenbush (who use the names Robyn and Rachel in their real lives) appeared on the Oct. 15 episode of the Little House on the Prairie 50th Anniversary Podcast with their former co-stars Alison Arngrim and Dean Butler and journalist Pamela Bob.

On Little House, Robyn and Rachel played Carrie Ingalls, the younger sister of Melissa Gilbert‘s Laura. They were credited as Lindsay Sidney Greenbush, as if they were one person. But in 1978, Little House on the Prairie aired the episode “The Godsister,” which starred both sisters on-screen at the same time.

Arngrim, 64, who played Nellie Oleson on the show, noted that their starring episode is “one of the most controversial episodes ever” with fans and often deemed one of the worst of the whole series. She said seeing the two actresses who played “Baby Carrie” on-screen at the same time was “freaky,” because it “never happens” in other TV shows.

In the episode, which aired in season five, Carrie doesn’t have any friends to spend time with, and her family wants her to leave them all alone. She slowly goes to the strawberry patch, where she meets another girl, Alyssa, who’s either an angel or a figment of Carrie’s imagination, who helps her have someone to spend time with. The hosts asked the Greenbush twins, 56, why they think the episode is so controversial.

“It goes really far away from the books and it enters like, fantasy, kind of ‘fairy godsister’ thing,” Robyn said. The series was loosely based on the book series by Laura Ingalls Wilder. “And I don’t think people were really ready for that.” She noted that “usually,” the things that happened in Walnut Grove, Minn., were more grounded in real life. “It’s really kind of a left turn from the norm of the show.”

Rachel added that she and her sister had “never been the story.” “It was a lot of pressure,” she said, adding that they also felt that pressure in their personal lives, because their mom was out of town and their dad, actor Billy Green Bush, was on set with them.

“My dad being an actor, he always thinks the rules don’t apply to him, and that’s a whole backstory. So there’s just a lot going on,” she said.

As for the logistics of the episode, Rachel shared that they both “traded off” playing Alyssa because both of them wanted to do it, though there wasn’t an even amount of scenes, so Robyn got to do a bit more.

Asked if it was odd to slip into a new character, Rachel said, “It wasn’t strange at all because as an actor you do different roles all the time. We were doing commercials and stuff.”

She added, “ I think even in our real life, it felt like we were stepping in and out of worlds, right? Because we’re going to regular school called Rachel and Robyn and then we’re stepping into the Little House world, and we’re Lindsay and Sidney. So it always is like just putting on different hats.”

Arngrim pointed out that it had to have been a nice change for them because Carrie was “ sort of like goofy, awkward, misfit, youngest child nobody wants to play with.”

“It was a nice change,” Sidney admitted, “and I think that’s why we both wanted to play Alyssa and why my mom felt it wasn’t fair to only let one of us do it.” She said they were both “eager” to play a different role.

Little House on the Prairie ran from 1974 to 1983. The cast also included Michael Landon as Charles Ingalls, Karen Grassle as Caroline Ingalls, Melissa Sue Anderson as Mary Ingalls and Victor French as Isaiah Edwards.

This year, Netflix released the first season of a new Little House on the Prairie series, which hews more closely to Ingalls Wilder’s books (while also adding new historical context). Season two, based on On the Banks of Plum Creek, finished filming earlier this month.