Fans who tuned in to The Talk on Monday (Oct. 14) got to witness a bit of show business history. New co-host Marie Osmond celebrated her 60th birthday on Sunday (Oct. 13), and her older brothers marked the occasion by giving their last-ever public performance as the Osmond Brothers.

Alan, Wayne, Merrill and Jay Osmond formed the first lineup of the Osmond Brothers, who got their start as a barbershop quartet and shot to fame during a series of regular appearances on the Andy Williams Show from 1962-1969. The four brothers reunited for a one-time-only trip down memory lane on The Talk, reminiscing about singing outside of their mother's room when she was in the hospital after giving birth to Marie because they were so excited about having a sister.

Marie introduced her brothers tearfully, explaining that the song they were performing, "The Last Chapter," is "a song they wrote to say 'thank you' to all of you, their fans."

They performed in front of a screen that displayed a video montage of personal and career highlights from Marie's life, and a split screen captured their sister wiping away tears as they sang. She joined them onstage afterward to pay tribute to them, saying, "I wanna say that I am so honored to be your sister. I love you guys. You've worked so hard. Enjoy your retirement."

Two other brothers, Donny and Jimmy, would ultimately go on to join their older brothers' group, re-inventing it as a pop-rock act in the '70s. Marie then joined Donny on a TV variety show, the Donny & Marie Show, which ran from 1976-1979 on ABC. She went on to significant solo success as a country singer in the '80s with songs including "Meet Me in Montana," "There's No Stopping Your Heart" and more. Most recently, she re-joined Donny for a long-running Las Vegas residency called Donny & Marie, which just wrapped in November.

See the Top 10 Country Songs of 2019:

More From Taste of Country