Image copyright AP Image caption Travis Rudolph said he was not aware the photo had been taken

The mother of an autistic child said she was moved to tears when a visiting American Football star joined her son, who was eating alone at school.

Travis Rudolph, a wide receiver for Florida State, was visiting a school in Tallahassee on Tuesday when he saw Bo Paske sitting by himself.

His mother, Leah, posted a photo to Facebook, where it quickly went viral.

She said that since that day her son had had no problem finding people to have lunch with him.

"This is one day I didn't have to worry if my sweet boy ate lunch alone," she said.

"He sat across from someone who is a hero in many eyes. Travis Rudolph thank you so much, you made this momma exceedingly happy, and have made us fans for life!"

Image copyright Leah Paske / Facebook Image caption Leah Paske's grateful Facebook post drew on her own difficult experiences at school

She also wrote about her memories of middle school being difficult, and how she worries about Bo.

"Sometimes I'm grateful for his autism. That may sound like a terrible thing to say, but in some ways I think, I hope, it shields him.

"He doesn't seem to notice when people stare at him when he flaps his hands. He doesn't seem to notice that he doesn't get invited to birthday parties anymore. And he doesn't seem to mind if he eats lunch alone."

She said the small moment captured in the photo has had a "huge impact".

Image copyright Getty Images Image caption Rudolph is a wide receiver the Florida State Seminoles.

The small act of kindness was picked up by both local and national newspapers. Rudolph, one of several players visiting the school that day, said he wasn't expecting the huge reaction.

"We just had a great conversation. He started off, telling me his name was Bo, telling me how much he loves Florida State. We went from there,'' said the West Palm Beach, Florida, native, now beginning his junior season.

"I just wanted to go say hi to the kid, because I saw him eating alone. I didn't even know anybody took a photo of it,'' he said. "I'm glad it can bring awareness to helping others.''

"It was real easy... you'd never think anything was wrong with him. He had a nice smile on his face. Just a really warm person."

Leah Paske says her son now has no shortage of lunch companions, and "everyone was super welcoming."

Bo was also excited by all the attention. "It's been awesome. Everyone was so proud of me,'' he said.