(Image Credit: Image credit: Courtesy Jay Groccia)

Lego toys often fill the days of little boys. But for 11-year-old James Groccia, the small, plastic building blocks fill his life.

The fifth-grader from Boylston, Mass., is so obsessed with Legos that he has spent the past two years of his life focused on adding one set in particular, the Emerald Night Train, to his collection.

In a YouTube video that has gone viral, James proved that determination pays off. And Lego's role showed the more-than-one-million people who have viewed the video why it is titled, "Why LEGO is the BEST Company In the World."

James, who has Asperger's syndrome, first discovered the Emerald Night Train set when he was around 8 years old and became "obsessed" with it, according to his dad, Jay Groccia.

"I told him, 'You know, it says for age 14 and above on the box, so it's probably a little complicated to build yourself, and I don't want to be building your toys,'" Groccia told ABCNews.com today. "I really wanted him to be able to do these things."

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Groccia and his wife, Karen, made a deal with their son that he could purchase the train set if he saved the money, figuring it would take him at least one year to raise the money.

Just as his parents expected he would, James diligently saved the money. When the family went to purchase the Emerald Night Train for James, however, they got a shock. Lego was no longer making the toy.

For James, settling on another Lego toy was not an option and he became focused on tracking it down, even though the train sets were now selling on websites like eBay for hundreds of dollars, something his parents deemed, "a little crazy to spend on a Lego set."

"I said, 'Well, you know, you write a letter to Lego and maybe one was returned and found its way back to their factory," Groccia said. "I told him, 'That's it James. If they don't have it, that's the end of the road.'"

On Sept. 1, James gave it a final go and sent a letter to Lego officials at the company's Denmark and U.S. headquarters pleading for an Emerald Train Set.

"I got another Lego set, thinking I could forget about the Emerald Night, but every time I see it anywhere on line I get very sad and disappointed. I still want the Emerald Night so badly, but there are none to be found. Do you have any at your corporate headquarters? … I have never wanted a Lego set so badly ever in my life," James wrote, signing the letter, "Your most loyal Lego fan."

Just two weeks later he got a letter back from "Thomas" in the company's Customer Service department with the seemingly devastating news that the company did not make the set anymore and his only option was to continue to search for it online.

Disappointed but undeterred, James kept telling his parents that he needed to "write another letter to Thomas," who "needs to find me one."

What James did not know was that on a day in mid-October while his mom was home alone she burst into tears after a FedEx delivery person dropped a brown package at their door. Inside the package, sent from Lego headquarters, was an Emerald Train Set, courtesy of the company.

"We were fully expecting them to say, 'Yeah we found one, write a check,'" Groccia said. "But the fact that thing just showed up at the front door like that, that was just a freak of a lifetime."

The Groccias knew they wouldn't be able to hold the set until Christmas but they decided to wait a few days until James' 11th birthday. On Friday, Oct. 19, after James and his younger brother, Michael, had come home from school, and with cameras rolling, they gave James the package.

"Yessss! The Emerald Night Train! I finally have it! Whoooooo!" James shouts in the video his dad, a commercial photographer, shot, edited and posted online that night for their family and friends, all of whom understand James' Lego passion.

One of those friends posted the video on Reddit and it's now been viewed more than 1.2 million times. One of those 1.2 million people was the man who created the Emerald Train Set James so coveted.

"I tweeted the video to their [Lego's] Twitter account and got a tweet back that the guy who actually designed the Emerald Train, in Denmark, got to see the video," Groccia said. "That was great."

James wasted no time putting the set together, his dad said, working on it up until dinner and after dinner on his birthday and then waking the next morning at 5:30 a.m. to complete it. He's taken it apart and rebuilt it several times since. For Christmas, James has asked Santa Claus to bring him a motor for the trains and tracks so he can complete the set.

"James probably will send them some kind of a thank you note," Groccia said, noting the family has not had any communication with Lego other than the tweet.

"This is big for him," he said. "For a week after, when he'd tell the story, he'd start crying. It's finally getting a little more matter-of-fact now. He was quite distraught about not having the toy."

"James is a really special kid," Groccia added. "He's got a wonderful, wonderful nature about him. He's a delightful child and he really tries to be the best boy he possibly can."