Nicole Richie Shares Teenage Throwback with Paris Hilton in Matching Fairy Costumes for Halloween

Frazer Harrison/Getty

Nicole Richie is reminiscing about simpler times this Halloween.

The Simple Life alum, 41, unearthed some throwback gold on Friday as she shared a black-and-white photo of herself and longtime pal Paris Hilton as teenagers, living their fairy princess fantasies for a joint Halloween costume.

"Happy Halloween," Richie captioned the photo, on which Hilton, 41, commented: "Sana saa! Love you Bill."

RELATED: Paris Hilton Has Simple Life Reunion with Nicole Richie at Her Wedding to Husband Carter Reum

Fans will recognize the comment as a callback to the gibberish song they made famous on their star-making reality show The Simple Life. The duo also has dubbed Richie's nickname as Bill and Hilton's as Sill.

Richie's trove of adorable Halloween throwbacks didn't end there, as she also took to her Instagram Story with a childhood snap of herself and father Lionel Richie acting out a kill scene, while he sports Freddy Krueger's hat and razor glove.

Another photo showed her then-preteen sister Sofia Richie dressed as a "punk rock cheerleader" and posing with Nicole's daughter Harlow Madden, who was still a baby at the time.

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

"Ps Your punk rock cheerleader costume will always be your most iconic," Nicole wrote to her little sis with the photo.

Meanwhile, Hilton looked to nostalgia for inspiration with her Halloween costume, sharing photos Saturday of herself dressed as Sailor Moon, while husband Carter Reum complemented her as Sailor's boyfriend Tuxedo Mask.

"Dressed up as my childhood icon Sailor Moon. Happy #Halloween!" Hilton wrote in the caption.

Nicole was there to support Hilton in November when she tied the knot with Reum, 41, in a star-studded wedding ceremony in Los Angeles. "Sill & Bill Forever. Thank you @NicoleRichie for sharing my special day with me. Love you! #Sanasa," Hilton wrote on Instagram at the time.

RELATED VIDEO: Paris Hilton Marries Carter Reum in Star-Studded Los Angeles Ceremony

The pair made their TV debut on Fox's 2003 reality series The Simple Life, which ended in 2007 on E! after five seasons. The show originally saw the pair bunking with the Leding family in Altus, Arkansas, where they experienced minimum-wage labor and farm life for the first time.

Although Hilton and Richie infamously had a falling out in 2005, which played out on The Simple Life, they've since mended their friendship and even given fans hope for a potential revival.