Jack Robbins suffers from severe autism. He's mostly nonverbal, and doesn't communicate emotion or create his own sentences. Only one person has helped him speak. Katy Perry. In this case, it's roar.

Robbins' parents began noticing their son repeating phrases and sounds and Jack's dad eventually realized that his son was singing to Katy Perry's popular song "Roar".

They recorded the performance and uploaded it to the Internet where it became instantly viral. Music can really be therapeutic.

“For all these years, I’ve cooked for him, I put things on him, I dress him,” Carla told Today. “I don’t know if he likes them or hates them. This is huge for me to finally know something that he likes.”

Watch him sing in the video below: