Stephanie Meade from Seattle, Washington first wrote to Muhammad Ali when she was 10 years old. More than 30 years later, they were still corresponding. Here, she tells BBC News about how these letters changed her life.
To the world, he was an incredible athlete and humanitarian - but, to me, he was just my friend Ali.
He has been the single greatest impact on my life.
When I was 10, I wrote a letter to Muhammad Ali.
Everyone told me that he would never write back - but, three weeks from the date of my letter, I received a handwritten letter from The Champ.
It reads: "Dear Stephanie, thanks for the sweet letter, one day I hope to meet you also. Tell all my fans I said, 'Hello,' from me. Kiss Mother and Daddy for me and wish them my love. May Allah always bless you and guide you. Love from Muhammad Ali.'
I didn't have an ordinary childhood.
My father became disabled when I was four, and so, when most children were out playing, I was sitting at home watching TV with him.
We would watch videotapes of Ali's fights.
By the time I was six, I could tell you details of every fight that Ali had ever appeared in.
When I went to school, my friends talked about Superman - but I always thought they were silly because I had Ali.
He was my own personal superhero.
I sent him my report cards and told him my deepest secrets.
Without fail, Muhammad Ali replied to every single letter, and I used to send him a new one at least once a month.
I would always tell him about how I really wanted to meet him, and he would always sign off his cards with: "I hope to meet you also, please tell Mummy and Daddy I said hello and God keep you and God bless you," before finishing with one of his famous boxing quotes.
This pen pal relationship continued for years until Parkinson's robbed him of his ability to write, but I still kept sending him cards and letters.
In 1992, when I was a struggling college student, I heard that he was going to be honoured in nearby Seattle, and I realised this would finally be my chance to see him.
I turned up outside the hotel where he was staying and told some of the security guards that "Ali writes to me" and begged them to show him my letters.
The next thing I knew, I was being escorted to the seat next to Muhammad Ali, right after Ali asked Mike Tyson to vacate his seat for me.
I finally got to meet my hero.
He was just every good thing you could imagine him to be.
By that point, his speech was slurred - but it was still incredible. And it turned out that during our gap in correspondence he had moved house, but he wrote his new address down on an envelope and told me to keep writing.
I sent him a card or letter about once a month, and he would have someone type up what he wanted to say.
In 2014, he was kind enough to invite my whole family to visit him at his home, which was also very special as it meant my disabled father could finally meet his hero.
I was telling him how very much I loved him, and, although he was unable to speak, his eyes were alive and he squeezed my hand and hugged me.
Yes, Muhammad Ali loved me back. I cannot put into words what that felt like.
Lonnie asked me to keep writing, as, she said, she would read my letters to Ali, and said that she knew they made him happy.
The world has lost the greatest athlete, champion, and humanitarian. I have lost the best friend I ever had.
It's true what he said - he was the the 'Greatest of All Time'. But he was an even greater man."
Stephanie will travel from her home in Seattle to Louisville to attend Muhammad Ali's memorial.
By Hannah Henderson & Andree Massiah, BBC's UGC Hub & Social News team