Dustin Snyder knows that he may have only days left to live.

For the past year and a half, the 19-year-old has been battling a rare form of cancer called synovial sarcoma — undergoing treatments to remove the tumors, only to watch them return and ravage his body.

Several weeks ago, doctors told him he had only weeks. So he turned to the person who had been beside him through it all — and asked her to spend the rest of that time with him.

“I love her. She’s been there for me through this whole process,” Snyder said about his childhood sweetheart, Sierra Siverio. Seeming to labor during a short Friday afternoon phone interview with The Washington Post, Snyder said Siverio “means the world to me. I wouldn’t be able to get through any of this without her.”

The couple married Sunday at the Big Red Barn, a farmers market with a private venue not far from home in Valrico, Fla.

“I wouldn’t want to be standing here with anyone else,” Snyder told his bride during the wedding ceremony,” according to CBS affiliate WTSP, “because you are the love of my life.”

“Sierra has given me the strength to keep up everything in my life,” Snyder told the news station, later adding that after his first surgery, Siverio never left his side. “That’s when I knew she was the one — and I didn’t want her to leave my life.”

Snyder’s mother, Cassandra Fondahn, said the couple privately discussed the idea of marriage earlier last week — a milestone that she hoped would make her son’s final days memorable. He has been at home, with regular visits from hospice, and a pain-medication pump connected to his heart, she said.

Snyder made the engagement official Thursday — treating Siverio to dinner, presenting her with roses and popping that special question.

He asked her to marry him.

Siverio, of course, said yes.

“She’s the woman I want to spend the rest of my life with,” he told The Post, days before the two tied the knot.

When word got out about the engagement, Fondahn said, Good Samaritans wanted to help — sending the bride-to-be wedding rings and a dress. A GoFundMe page created by his sister has raised nearly $40,000.

“He really wants to marry the woman that has stuck by his side through all the sleepless night and now dealing with knowing he will pass any time soon,” the GoFundMe page says. “Dustin always said ‘She is a Keeper.’ Please lets help Dustin enjoy the rest of his life with his soul mate.”

An update to the GoFundMe page said the family had reached its crowdfunding goal for the wedding and that additional funds would go toward bills — and “the cost for when the day comes for Dustin to be at rest.”

“He will not have to worry about money,” the page says. “We are about to start trying all of the new remedies that a lot have people have been sending. 1st being Pulsed Electromagnetic Field Therapy. With the generous donation it helps a lot on the cost. We will try to fight this, it’s not over.”

Posted by Brittany Hails on Sunday, January 28, 2018

It was a Monday in June 2016 — a day before his 18th birthday — when Snyder got the news.

Doctors discovered the cancer in his left lung, which his mother said is rare. Synovial sarcoma is a slow-growing cancer that typically attacks the soft tissues near large joints and, in some cases, is initially misdiagnosed as arthritis or bursitis, according to the Mayo Clinic. Sometimes, however, it can develop in the kidneys and lungs.

“The goal is to remove the cancer and a margin of healthy tissue around it,” according to the clinic. “This can sometimes mean the removal of an entire muscle or muscle group, or even amputation.”

Snyder’s mother said he underwent chemotherapy and radiation “hoping to save the lung.” But several months later, doctors had to remove it.

Following more chemo and more radiation, Snyder was cancer-free in January 2017, his mother said. The prognosis was good, she said, assuming her son’s cancer did not return. But by August, she said, doctors had found three more spots.

After that, Fondahn said, “we were told that it would keep coming back until they couldn’t treat it anymore.”

More surgery.

Then more good news — until about a month ago, when Fondahn said her son started to feel ill and lose weight.

The cancer, she said, had taken over his stomach and pelvic area.

“That’s when they told us that this was the final deal,” she said.

“We weren’t expecting it this fast,” she added, “so it was very emotional, very hard to take. He’s a very, very strong young man. He’s a fighter, and he has this whole time been fighting through all of it.”

Several weeks ago, Fondahn said, doctors said Snyder had only weeks to live.

“He’s getting worse,” she said Friday, explaining that his hospice team keeps having to increase his pain medications. “He’s getting weaker and tireder.”

“He got a small burst of energy since this whole wedding thing came about,” his mother added. “We’re really hoping that Sunday gets pulled off for him.”

Snyder and Siverio have known each other since middle school and even “dated” for a time back then, Fondahn said with a chuckle. But the pair lost touch when Snyder was moved to a different school district. It wasn’t until about two years ago that they found each other again — when Siverio spotted him working at a local Steak ‘n Shake, Fondahn said.

“Every minute of this, she has been by his side,” Fondahn said.

“As a mom, I want him to be happy during his final days — whatever that is that makes him happy,” Fondahn said of this weekend’s wedding. “I don’t think this will change anything dramatically for either one of them; it’s just going to make both of them happy. And that’s what it’s all about.

“She’s going to get the wedding of her dreams to the man she loves, and he’s going to be at peace knowing he has his soul mate with him when he goes.”

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