The tragic story of how teen TikTok star Anna Grace Phelan documented her terminal cancer battle has left millions heartbroken as tributes pour in.

Phelan, 19, captured hearts across social media as she bravely documented her battle with a grade 4 malignant brain tumor.

She shared intimate moments of her fight right up until her final days.

The inspiring influencer's family announced her heartbreaking death on Friday, May 23, just one week after she posted a gut-wrenching final update about her deteriorating condition.

'Things haven't been good. My tumor grew and it's in the area where I can't breathe and it can't be operated,' she said. 'So, I just want to say thank you for all the prayers. It would take a miracle, but I'm not giving up yet. If you keep praying for me, I think that I'll make it.'