Photo: Frazer Harrison/Getty

HOLLYWOOD, CA - APRIL 14: Nicole Richie and Paris Hilton (L) aririve for the “Simple Life 2” Welcome Home Party at The Spider Club on April 14, 2004 in Hollywood, California. (Photo by Frazer Harrison/Getty Images)

Nicole Richieis reminiscing about simpler times thisHalloween.

TheSimple Lifealum, 41, unearthed some throwback gold on Friday as she shared a black-and-white photo of herself and longtime palParis Hiltonas 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.”

Fans will recognize the comment as a callback to thegibberish song they made famouson their star-making reality showThe 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 fatherLionel Richieacting out a kill scene, while he sportsFreddy Krueger’s hat and razor glove.

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“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 husbandCarter Reumcomplemented her as Sailor’s boyfriend Tuxedo Mask.

“Dressed up as my childhood iconSailor Moon. Happy #Halloween!” Hilton wrote in the caption.

Nicole wasthere to support Hiltonin November when shetied the knotwith 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

Although Hilton and Richie infamouslyhad a falling outin 2005, which played out onThe Simple Life, they’ve since mended their friendship and evengiven fans hope for a potential revival.

source: people.com