The group will climb Ben Nevis on Sunday August 22 to raise money for the Thalia-Beau Foundation and to raise awareness of organ donation.
Thalia suffered from restrictive cardiomyopathy - a rare condition which meant she needed a new heart and lungs.
She was on the urgent list for a transplant and her doctors, including a team at Great Ormond Street Hospital in London, were doing everything they could to try to find her a donor but she tragically died whilst waiting.
Katie Newton, one of the climbers, said: "I wanted to mark the year anniversary of Thalia passing away.
"[The climb] is to remember her and raise awareness of organ donation.
"We want to raise as much money as possible."
Katie was part of a group of people from Barbelle gym who climbed Mount Snowdon in 2019 to raise money for a fund to send Thalia on a once in a lifetime trip to Disneyland Paris.
The group's target is £2,000 and they have been practising as often as they can, including a climb at Roseberry Topping.
When they arrive in Scotland they will be staying in Fort Augustus, where they have been offered accommodation for free after the owner heard about their challenge.
The money raised will be donated to the Thalia-Beau Foundation which was founded in November 2020.
Initially the charity aims to provide care packages to those families and children who are experiencing long term hospital visits and to continue to raise awareness of organ donation.
For more information about the foundation visit the website here.
To donate to the Ben Nevis climb visit the JustGiving page here.