Vine star Hayes Grier joins 'Dancing with the Stars'

Vine star Hayes Grier will compete on Dancing with the Stars season 21.

The 15-year-old social media star revealed the news on the Challenged app Thursday morning. Grier joins 35-year-old Backstreet Boys singer Nick Carter, 17-year-old conservationist Bindi Irwin and 43-year-old Triple Crown jockey Victor Espinoza.

"It's going to be really cool and an amazing journey to be on season 21 of Dancing with the Stars," he announced. "I'm super excited and I really want you guys to be a big part of it and support and vote for us. It's going to be a great time."

The news comes amid word legendary funk singer Chaka Khan and celebrity chef Paula Deen will also take part. ABC Action News anchor Dan Shaffer dismissed such reports as "just rumors," saying he will let fans know if an official announcement is made.

Grier is known for his posts on Vine and YouTube, which include his viral Lemon Challenge video. Dancing with the Stars season 21 will premiere Sept. 14 at 8 p.m. ET on ABC, with returning pros Derek Hough, Karina Smirnoff and Val Chmerkovskiy.