The 54-year-old Hollywood star, who played Rachel Green in the sitcom which ran from 1994 to 2004, reconnected with actress Mae Whitman – some 27 years after they worked together on the show.
Whitman, now 34, was just eight when she appeared in an episode called The One Where Rachel Quits.
She played a girl scout who is accidentally knocked down the stairs by Ross Geller, played by David Schwimmer.
To make amends, the character helps her to sell boxes of her cookies. In the episode, Aniston’s Rachel also quits her job at Central Perk coffee shop – hence the name.
The pair met again on an episode of Live With Kelly and Ryan, where Witman said to Aniston: “I was on Friends. I played the girl that gets knocked down the stairs with the Girl Scout cookies.”
Aniston reacted in shock, saying: “Oh my God!”
Whitman continued: “I just wanted to say hi because you were so kind to me. It was my favorite show and you really made me feel like I was a part of the cast. And you were so kind and you hugged me. Thank you. It’s always stayed with me.”
Whitman said to Kelly and Ryan: “I’m 8 years old, I think. And I got a call that I was cast on Friends, and it was my favourite show at the time. Why an eight-year-old loved Friends, I can’t tell you, but I found something relatable in there.
“And I remember Jen was so kind to me, she made me feel like I was part of the cast and she took such good care of me, and I wept hysterically when I wrapped.”
She continued: “And I made her a Christmas ornament with her name on it. That was the first time I’ve seen her. That was a big reunion. That felt amazing to see her. She’s so cool. Such a cool person. The universe has its ways.”
Whitman also shared pictures of the reunion on her social media pages.
She wrote: “Had the genuine best time doing @livekellyandryan [...] The coolest part was I had a Friends reunion with the luminous @jenniferaniston whom I remember made me feel so welcomed and loved and I wept hysterically when I wrapped the episode and made her a Christmas ornament.”
Jennifer Aniston - In pictures
Aniston was recently supporting her Friends co-star Courteney Cox as she was honoured with a star on the Hollywood Walk of Fame in Los Angeles.
Cox is well known for playing the neurotic but loveable Monica Geller in the hit US sitcom.
She is also a renowned producer and director.
Cox was joined at the ceremony on Monday by members of her family, as well as Aniston, their Friends co-star Lisa Kudrow, and Hollywood actress Laura Dern – all of whom gave remarks.
Recalling in disbelief their work on Friends almost 30 years ago, Aniston and Kudrow praised Cox’s work ethic and “warmth”.
“We’re very honoured to be here today to speak on your behalf as your co-workers, your friends and your family. Your sisters,” Aniston told her.