A boy with autism said he wished to make friends. On his birthday he got more than 55,000 messages from people around the world.

Daniel Harrison, who has autism, recently wrote down two wishes – and one of them came true.

"Daniel, for the first time, was asked at his special needs school to write two things that he'd like to achieve," Daniel's dad, Kevin Harrison, told CBS News. "His first was learning to drive and the second thing – which surprised us – was 'make some friends,' because we didn't understand that he understood the theory of friendship."

Harrison, who is from Nottingham, England, said children on the autism spectrum often want to play alone, and Daniel has never expressed wanting friends. "So, that shocked us to the core, really," he said.

Harrison often shares updates about Daniel on social media and has gained a small following for his autism awareness posts on Twitter. But one post on Daniel's 15th birthday stood out. 

"Daniel's my son. Profoundly Autistic. Hasn't one friend. It's his birthday today," Harrison wrote, encouraging people to wish him a happy birthday and show him they care.

The post began racking up likes and replies, snowballing until it was the number one trending topic on Twitter for the U.S. "I'm sitting there thinking, 'What on Earth have I done?'" Harrison said. "And a lot of that was down to Mark Hamill, from 'Star Wars.'"

Hamill, known for his portrayal of Luke Skywalker, was one of the first celebrities to tweet a happy birthday message to Daniel. His tweet alone received more than 17,000 likes.

Harrison listed Russell Crowe, Sharon Stone and Ariel Winter as other celebrities who tweeted to Daniel – but many of the replies were from parents of children who also have special needs. 

"He's got four friends in Minnesota and one with #autism whose name is Daniel too," tweeted Sheletta Brundidge, sharing a photo of herself and her son. 

"Hey Daniel, this is my son Jacob, also autistic, on his birthday last month," wrote another dad who also shared a photo. "I'm sure he would love to be your friend if you met, provided you don't mind hearing a whole lot about superheroes. Hope you had a wonderful day."

Harrison was shocked by the overwhelming response – but knew why the story resonated with so many. "People want to be loved, don't they? People want to be liked. It's a universal feeling," he said.

"I think it's a good news story, because the whole world right now is polarized," Harrison said. "Everywhere, there's no middle ground. Yet, we found with Daniel's tweet and the story that there's a lot of beautiful, lovely people in the world." 

The dad said some of the responses he showed Daniel made him jump for joy. "It made me happy for Daniel, but you know, it's made me happy for parents and families and friends of autistic people across the globe," he said.

As for Daniel's other wish – to drive a car – Harrison says Daniel likes to play "Mario Kart" on Nintendo, and that's as close as he'll get to driving for now. 

He hopes the countless people who heard about Daniel's story remember one thing: "Don't ever feel like you're alone. Because I felt like that, and I know other families will. You're not alone. Just simply that, people do love you."