Fourteen year old Jerika Bolen, from Wisconsin, US, suffers from spinal muscular atrophy - a disease that causes constant pain and prevents her from using most of her muscles.
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Earlier this summer she posted a goodbye video informing the world of her decision to end her life, with the support of her family.
Jerika said: "When pain is too much, it's too much. I need to do what's best for me... It was a really hard decision to make."
After seeing the heart-breaking clip, 23-year-old Jordan Schroeter, who suffers from the same incurable disease, felt he had to respond.
He says: "If you're watching this Jerika Bolen, please don't do this, please reconsider your decision. Regardless of what you feel, your story is not over. I know what it feels like to be in that dark place... You are a woman of worth and value and now is not the time to leave this world."
Jerika has been confined to a wheelchair for as long as she can remember and is unable to move most of her body.
Her mother, Jen Bolen, confessed that the option to end her life had been discussed for several years, as most people with the disease don't survive as long as her daughter has.
Jen said: "I knew it was coming, but I also realised that she fought much longer than she would have if it weren't for her trying to protect me."
On 22 July, Jerika's family held a special prom for their daughter as her last wish. The event was open to the public.
"I don't have many friends. I'm not like, because I couldn't get out really and do many things because I was in so much pain, and this prom is, well, we call it my last dance," explains Jerika.
Sometime in late August, Jerika plans to stop using a ventilator she currently uses to breathe.