The 31-year-old Olympic gold medallist appeared on the Late Late Toy Show on Friday night where she surprised two of her super fans named Darcy and Poppy.
Taking to Instagram, Kellie said that watching the annual Christmas show, presented by Ryan Tubridy, is part of her family tradition.
“So about last Friday,” her post began.
“I got to meet these two absolute best friends Darcy and Poppy. They were full of energy and joy. The @latelaterte toy show is a show I have watched every year since I’ve been a kid, and I absolutely love it.”
“It is all about the children, and for me it is all about good memories that were made watching it back as a child and hopefully one day when I have children of my own starting that same tradition with them and giving them the same fuzzy feeling inside as I did when I was a kid getting ready for it and watching it,” she explained.
“The Toy Show is a tradition that many families have together, a tradition filled with love, joy and happiness after a belly full of sweets of course.”
The Dubliner surprised the young girls with signed boxing gloves and merchandise, as well as offering to give the girls boxing lessons at their school.
Kellie, who has been in a relationship with her girlfriend Mandy Loughlin for 13 years, met through their mutual love of boxing.
Speaking to Ryan Tubridy about their relationship earlier this year, she said their connection was instant.
“We met 13 years ago in boxing when she used to have to trek over to Bray to train where I was training at the time. We met there and clicked and the rest is history. There was an initial [vibe that they wouldn't get along] the first time we met but after that we were grand.”
“I suppose it's just such a difference - a north inner city girl and a southside girl might just not get on straight away but opposites obviously attract and it was the best thing ever,” she said of their romance.
Mandy, who no longer competes in boxing competitively, showed huge support for Kellie as she competed at the Tokyo Olympics earlier this year.
Chatting to Ryan Tubridy, Mandy said she was too nervous to watch her fights live.
"I just can't do it. I don't know whether it's because I've been a boxer myself... I don't know. I just don't know. I just can't do it,” she said.
Mandy revealed she had sleepless nights during the competition.
"Usually I take the dogs out for a walk or I try and just be normal and do normal things just to try put it at the back of my mind for awhile. It was actually hard because they were all in the middle of the night this time so it was just sleepless, anxious nights.”
“It was really, really, really tough I have to tell you,” she added.
When Ryan asked if she thought Kellie would win gold at the event Mandy said: "I never doubted Kellie for a minute. Never.”
"The whole package is here for Kellie now. She's got such a fantastic support system in her coaches, in the IABA, in her club coach, her family, her friends.”
"Everything has just come together so well for Kellie. Obviously Covid and stuff like that has kind of not knocked her confidence, but I feel the only thing that wasn't coming together was the lack of preparation to a certain extent where they weren't going to the usual competitions at that level.”
Kellie went all the way, and managed to bag gold for Ireland in the lightweight boxing division at the games in August 2021.
She returned home to Dublin receiving a hero's welcome at her residential area of Portland Row in the inner city.