The singer, who worked alongside Flack on The X Factor, stylists Lou Teasdale and Nana Acheampong, and close friend Mollie Grosberg will also join the walk.
Led by the late Love Island presenter’s personal trainer Bradley Simmonds, the group will climb 24 peaks in 24 hours to raise awareness and funds for the suicide prevention charity.
They will trek 12 hours each day across the Lake District and scale England’s highest mountain, Scafell Pike.
Caroline took her own life at the age of 40, on February 15, 2020.
Olly announced the trekking news in a post shared to his Instagram, which he captioned: ‘Hi guys, I’ll be taking part in #Climb4Caroline in memory of Cazza this weekend.
‘A few of us will be trekking 24 peaks in 24 hours to help raise awareness and hopefully help raise vital funds for leading suicide prevention charity, @samaritanscharity. If you’d like to support click on the link in my bio!’
Speaking in a statement, Caroline’s family said: ‘Thank you to everyone taking part and to those at home who are supporting us. Good luck and thank you for taking the time to raise vital funds and awareness for Samaritans.’
Meanwhile, Caroline’s personal trainer Simmonds added: ‘I was Caroline’s personal trainer and good friend. I was devastated at the loss and still am.
‘I know how much exercise helped Caroline with her mental health so I wanted to create a challenge where her family and friends can come together and do something powerful in her memory.
‘Hopefully, this challenge will raise awareness for others to seek support whilst also raising money for Samaritans,’ he said.
Sarah Ball, head of fundraising at Samaritans, added: ‘We are extremely grateful to Bradley for choosing to raise vital funds for Samaritans, which will help us be there at any time of day or night to support anyone who is struggling to cope.
‘Suicide is complex and every single death by suicide is a tragedy that devastates families, friends and communities.
‘We wish Bradley and Caroline’s friends and family the best of luck on the hills with their fundraising challenge.’
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