Texan seven-year-old girl Bella, who is undergoing treatment for brain cancer, was Mooy's guest of honour for Huddersfield's match against Leicester after joining the player she calls her 'hero' to lead the Terriers onto the pitch.
Her family had travelled from the United States so Bella could meet the player who has inspired her since she first saw Mooy play for Australia during the 2018 FIFA World Cup in Russia.
Bella's father Scott said it was a moment he will never forget, thanking both Mooy and Huddersfield for granting his daughter such an incredible experience.
“He and Huddersfield have made a little Texas girl’s dreams come true," he said.
The story behind Bella's love for the Australian player is a touching tale.
Waking up in her father's arms after falling asleep watching Disney movies, Bella awoke while her dad turned on a World Cup match involving the Socceroos.
"I like him. He is like me," Bella declared, pointing to her own head, shorn of what had been long, beautiful curls by powerful chemotherapy treatment.
The fleeting moment became an obsession for young Bella, who has followed Mooy's fortunes with club side Huddersfield.
A post on Instagram of Bella in her Huddersfield jersey went viral and caught the attention of the Socceroo himself, who reached out to his young fan and invited her to travel across the Atlantic and meet him in person.
A visit to Huddersfield's training session at their Canalside training ground was followed by a seat at the John Smith's Stadium during the 4-1 defeat to Leicester.
However, the result meant nothing to Bella, who was all smiles after leading the team onto the pitch hand-in-hand with hero Mooy, before watching him score from the penalty spot.
“This is the privilege of the job,” said Mooy.
“You can help in a lot of different ways. She got some sort of joy out of watching me play at the World Cup. Now she is a Huddersfield fan and she came to the match, which is amazing," father Scott said.
“This season has been tough for the club, but bringing Bella here has picked everyone up a little bit. That is the thing that made me happy today.”
