FLORISSANT, Mo. (NBC) – An 11-year-old from Missouri is getting cards from across the country as he battles a rare deadly disease.
Alex Sims hopes you will send him a holiday card and sign up for bethematch.org to save his life, or hundreds of others.
Alex doesn't just read holiday cards; he hangs on every word.
"I know when Alex gets something in the mail, something with his name on it and a stamp, it just brightens his day," said Brandon Sims, Alex's father.
Especially this time of year, Alex's days need brightness.
"But because of his disease, we have to be very careful with the flu, colds and viruses out there," Brandon said.
A few years ago, Alex was diagnosed with a rare autoimmune disease called immunodysregulation polyendocrinopathy enteropathy X-linked, or IPEX.
"His immune system overresponds when he's sick," Brandon said. "Not only does it attack germs and viruses, it also attacks the healthy organs in his body."
And without a miracle in the next few years, Brandon says, "eventually it will attack so much of his healthy tissue, he won't be able to survive."
Keeping germs at bay means often Alex doesn't get to go play. That's when Alex's dad delivered his best idea yet.
He asked his Facebook friends to write Alex a Christmas card for the 25th and a birthday card for the 26th.
He expected a dozen or so. So far, he's gotten 200.
A common theme in a lot of the letters is the author wishing he or she could do more to help Alex.
It turns out, there is more to be done. A bone marrow transplant could replace the gene that wreaks havoc on Alex's immune system.
"That one-in-a-million person is out there," Brandon said. "… With that bone marrow donation, it's his only chance of surviving."
So, Alex hopes before you send, you'll swab. And if you decide to do so, Alex has a message.
"I'd say, thank you so much, it's so cool, I love it," he said.
If you would like to send Alex a card and sign up to see if you would be a good bone marrow donor for him, visit cota.org/campaigns/cotaforteamalexs.
For Alex's address, visit the original story.