How do you help your child die? What kind of disease could wreak such horror on a little body that in the end, a mom who fought so hard to keep her daughter in this world would pray she'd give up her battle to live? What do you say to a terrified 8-year-old who tells you again and again that she doesn't want to die when you know she's going to pass away?

There's no textbook, so Amy Potvin wrote one for the whole world to read. Using a website (www.caringbridge.org/visit/elliepotvin) and Twitter, Potvin, who lives in Charlotte, recorded in heart-wrenching detail her daughter Ellie's battle with a rare form of cancer called Rhabdomyosarcoma. Hundreds of thousands of people the world over quickly fell in love with Ellie online and pulled for the family, who dubbed themselves "Team Potvin."

"I have never known any child was capable to fight this hard to cling onto life," Potvin blogged the morning of her death. "I am exhausted watching her body heave up and down for air. She has bubbles in her throat and wheezing ... Earlier as she struggled, she woke in a daze to see me crying next to her. She was barely audible, but I understood she wanted the anointing oil. This is from Lourdes. I handed it to her ... Our Ellie anointed my forehead with the cross and said, 'Mommy it is OK. I am OK.' This child is an angel who specializes in kindness till the end."

And then this: "Ellie is barely with us in body ... All is failing. She can barely speak, sleeping in and out. She woke to see my tears and did the most incredible Ellie thing ... She made us laugh and smile. God knows how she slowly managed to kiss her biceps and say 'don't worry I am strong Mommy. A fighter' ... Breathing is slowing down ... Angels I pray she will hear call her name. As much as I love her ... Stop this fight. Ellie has won the prize. Heaven."

And then: "Enough God ... Ellie's body has been tormented ... Please God! Let her soul be free."

And then, hours later: "Ellie is still breathing ... She is ever so slowly leaving us. This is breaking me to shreds, I have been ripped apart, this has tested my faith, to watch your child die before your eyes -- is too much for a mother -- just too much. God I pray ... Please let her fly."

And then, at 11:42 a.m. on June 23, this message went out to the multitude of people who have signed up to follow Ellie's struggle: "Ellie gained her angel wings at 11:35 a.m. and rests in my arms."

It was sent a remarkable seven minutes after her daughter's death. To those who have followed Ellie's struggle with cancer, that made sense. And that's what makes this story so remarkable.

In the beginning, Amy Potvin clearly didn't set out to chronicle her daughter's inspirational two-year fight for life, which would eventually touch millions, for the sake of doing it. The plan was to use her faith in God and the prayers and good wishes of thousands of people to "lift up Ellie," as the movement came to be called, and help her battle odds that said she had just a 30 percent chance of survival. (It also included a fundraising arm to help pay the mounting medical bills.)

As you got to know Ellie, and to be awed by her, it seemed impossible that a loving God would allow her life to be cut short, or to end in the physically agonizing way that it did. When the answer the Potvins got was not the one that everyone prayed and wished for, not the one Amy and Ellie seemed so certain of for months, thousands instead watched a soul-wrenching test of faith in both mother and daughter. It is the most remarkable story I've ever read -- and as journalist, that's saying a lot. Whatever you take away from it, you simply cannot read it and not be changed in some way. In the end, Amy Potvin's greatest triumph was that through sheer force of will she gave her daughter a life -- and a death -- that was not in vain.

In the hospital, after the births of both of my children, they wheeled me out of the delivery room and let me push a button that broadcasts a short recorded lullaby to everyone on the maternity ward, an announcement that another baby had been born. Given the sheer magnitude of the miracle I had just witnessed, that seemed absurdly understated. Never before had there been a child like this one, and never would there be again. It seemed there should be a celebration with marching bands and a laser light show. There should be ticker tape, fireworks and jets roaring overhead.

In the end, Potvin gave her daughter just that. She grabbed millions by the nape of the neck and made them realize the value of a unique, beautiful little life, and in the process, the value of their own lives and the lives of those they love.