The heartwarming moment Taylor Swift grants a young girl with terminal cancer a special wish at Sydney concert: 'The sweetest thing!'

Taylor Swift made a terminally ill nine-year-old girl's dream come true on Friday.

At the first of her Sydney shows on her Eras tour, Swift chose young Scarlett, who is fighting an aggressive form of brain cancer, to be the recipient of her signed '22' fedora.

Taylor has established a tradition where she gives a signed hat to one lucky fan in the crowd while singing her song, 22.

Earlier on Friday, Scarlett's step-mother Natalie had posted to social media that her step-daughter's wish had been to meet Taylor.

'Scarlett was granted a "Wish" from the Make A Wish Foundation and her wish was to meet Taylor Swift,' Natalie wrote in the post.

Taylor Swift made a terminally ill nine-year-old girl's dream come true on Friday. At the first of her Sydney shows on her Eras tour, Swift chose young Scarlett, who is fighting an aggressive form of brain cancer , to be the recipient of her signed '22' fedora (pictured) 

'Unfortunately, they told us this wasn't possible so through the power of social media and some generous people we made attending the concert happen and got tickets.'

She then shared a picture of Scarlett, who has been given just 12-18 months to live, holding a poster that read 'Taylor can I have the 22 hat please?'

Later at the concert, the young girl's wish was Taylor's command.

The singer invited Scarlett up to the stage, embraced her while she handed over the fedora, then tenderly kissed her hands.

The singer invited Scarlett up to the stage, embraced her while she handed over the fedora, then tenderly kissed her hands

Footage of the moment was shared on social media, and many fans expressed joy at the heartwarming scene.

'Sobbing,' wrote one, while another posted a series of crying emoji.

'It's the sweetest thing!! She deserves it so much!!' said another Swiftie.

'Aw they chose the right Swiftie,' wrote one more, while another declared 'Not even there and me and my sister are in tears.'

'Bawling my eyes out. So precious!' another expressed.

Swift is set to perform four shows in Sydney from Friday, February 23 through to Monday, February 26. 

Taylor has established a tradition where she gives a signed hat to one lucky fan in the crowd while singing her song, 22