Ally Brooke is bringing joy to one of her biggest fans. 

The singer surprised Caitlin, a teenage blood cancer survivor, as part of The Leukemia & Lymphoma Society’s Random Acts of Light movement.

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Caitlin, 16, turned to music when she was diagnosed with blastic plasmacytoid dendritic cell neoplasm (BPDCN) at the age of 12.

Following a stem cell transplant, the brave music fan listened to tracks by Bruno Mars, Meghan Trainor and Fifth Harmony to get her through 100 days of isolation.

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One of Caitlin’s favourite songs to play was Fifth Harmony’s “BO$$”, which she said “brought light to my parents and all the nurses who saw” her sing it. 

“I’m so honoured that I and we could be such a beautiful part of your journey to give you so much light and hope and joy in such a hard time in your life,” said Brooke in the video chat. 

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She added, “One of my favourite Fifth Harmony songs was ‘BO$$’ because it was so empowering, and that is so special to me, honestly, that our song helped you. So that’s something that’s so beautiful and I’ll remember always.”