Cassie Gretchel was facing "mission impossible" this holiday season, but with a little help from the internet she pulled off a Christmas miracle.

Cassie's younger brother, Max, was born with Cerebral Palsy, scoliosis, and a developmental disability. He's also visually impaired, and relies on a wheelchair to get around. Max is 25 years old, but according to Cassie he has the mental capacity of a five-year-old.

That means Max loves children's toys, especially Tonka trucks. But his interest in the toys is very specific. Cassie says that "literally the only thing" Max will play with is his Tonka Police Hummer truck, which the company stopped making in 2000.

To make things even tougher, Max is picky about the color too.

"They used to be really easy to find because we would just get orange ones," Cassie explains, "and then I made the mistake of finding a blue one on eBay and now he only wants blue ones."

Cassie and her parents scour eBay for every Hummer truck they can find, and buy up lots of backup trucks because Max plays with them for hours each day. But his year, Cassie was having trouble finding a new truck for Max to open on Christmas morning.

But when group of strangers stepped in, everything changed.

Cassie says she was feeling "a little desperate" after her latest hunt for Max's favorite truck fell through.

"I never want to let him down," she explained, so she took to the internet looking for more trucks. She also shared Max's story on Reddit, and asked readers to let her know about any Hummer trucks they had sitting in their homes.

People were touched by Cassie's heartfelt search, and many readers found more trucks right away. Some even bought the trucks off Amazon and eBay, telling Cassie they would ship to the toys to her home for free.

But the best twist of all in this heartwarming story came when people let Tonka know about Max and his love for their products.

"We love hearing stories like this and we will do everything in our power to help. We currently have our team searching through our warehouse archives in the US and China for the 2000 Fire Rescue Hummer," they wrote.

"We hope to be able to send them as many as we can find as well as a giant Tonka care package. Giving is the true spirit of Christmas, and we would not be where we are today without our fans and customers."

Cassie admits she didn't expect her story "to go this crazy," but of course she's grateful that Tonka is willing to help her brother. She was simply "trying to find a lead" to make sure Max had a merry Christmas, and now the whole world is touched by her story.

Share this sweet story with someone you know!

[H/T: BuzzFeed]