"Old Town Road" is reaching millions with its new country sound, and now the chart-topper may have just worked a miracle for an autistic child in Minnesota.

Sheletta Brundidge, host of the podcast Two Haute Mamas, has four children, three of whom are diagnosed with autism.

She said her children, like many others in the nation, love Lil Nas X and Billy Ray Cyrus' hit song, so much they play the song off the family's karaoke machine almost constantly and have their own "Old Town Road" concerts.

"I hear 'Old Town Road' probably eight hours a day," she told the Tennessean. "They wake up and listen to it, and they go to bed and listen to it. It's literally playing right now. ... It's pretty much a part of our family."

All of Brundidge's children are fully verbal except for her youngest, Daniel,4.

She said her children with autism have been enrolled in speech therapy from an early age, and Brandon and Cameron "made wonderful progress."

Daniel, however, struggled more than his siblings.

"He just hasn't responded well to the therapy. Nothing we've tried has given us the results that we saw with the other children. ... We were beating our head up against the wall."

In the past week, however, something changed for Daniel thanks to "Old Town Road."

Brundidge and Daniel were at their house in Cottage Grove, Minnesota, when Daniel began to hum the tune of the song

"It was just a hum at first," Brundidge said. "I was like, 'Oh my god, he's singing 'Old Town Road.' Then he started saying the words. This is a child who hasn't said three or four words together in the time he's been alive."

Brundidge said she began to cry when she heard Daniel singing. She called her husband down from upstairs and filmed a video of Daniel with her phone.

"It's such a breakthrough. It took us six months for us to teach him the letter A. Without any teaching, he was able to listen to it, absorb it, memorize it and then recall it."

"All this money we spent on therapists and doctors and supplements ... and 'Achy Breaky Heart' is the one who brought my son the breakthrough that he needed," referring to Billy Ray Cyrus by the name of his breakout 1992 country hit song.

Immediately afterward, Brundidge called a meeting with Daniel's therapists to discuss what had occurred. She asked them to incorporate the song in her son's therapy going forward.

Brundidge said the family will also be incorporating music therapy into Daniel's daily routine, hoping to replicate the success they found with "Old Town Road."

After Daniel's breakthrough, Lil Nas X himself responded via Twitter, referring to Daniel as a "king."

Lil Nas X recently brought the hit song to this year's CMA Fest with Billy Ray Cyrus, and Cyrus is scheduled to perform Saturday night in Nissan Stadium.

Reach Andrew Wigdor at awigdor@tennessean.com and on Twitter @andrew_wigdor