CNN) — Add music therapy to the list of “Old Town Road’s” accomplishments. The crossover hit by rapper Lil Nas X has burned up the charts and started conversations about the definition of country music.

Now a mom is saying it’s helped her mostly nonverbal autistic son find his voice.

Sheletta Brundidge of Cottage Grove, Minnesota, recently tweeted a snippet of a video showing her 4-year-old son Daniel humming and singing the tune.

The video went viral and even caught the attention of the rapper, who RTed it and wrote “what a king.”

Country star Billy Ray Cyrus appears on the remix of the song and also retweeted Brundidge.

Brundidge, 47, is a producer at WCCO Radio and host of the “Two Haute Mommas” podcast. She told the Pioneer Press that she and her husband Shawn, 53, have four children: Andrew, 12, Brandon, 6, Cameron, 5, and Daniel.

NASHVILLE, TENNESSEE – JUNE 06: Lil Nas X and Billy Ray Cyrus visit the Spotify House during CMA Fest at Ole Red on June 06, 2019 in Nashville, Tennessee. (Photo by Terry Wyatt/Getty Images for Spotify)

The three youngest children have all been diagnosed with autism and Brundidge said Daniel has struggled, taking six months to learn the letter A.

So she was shocked, she said, when her youngest started in with the song while she was cleaning their kitchen.

“He starts humming,” she said. “I’m like ‘Am I a crackhead or is he humming ‘Old Town Road?’ Then he started singing the lyrics.”

Brundidge said she texted her husband to come to the kitchen and became overwhelmed by what was happening.

“I started crying. The tears were coming down and landing on his head,” she said. “He started patting the top of his head. It was just full of slobber and snot and tears because I couldn’t stop crying. We’ve been praying for this boy since he went down. This is an answer to my prayers.”

The song has also proven to be pretty popular with listeners of all ages.

It became a viral hit after it found love on the TikTok app, where users create and share video clips set to music.

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