Demi Lovato was scheduled to perform on Fourth of July at Philadelphia’s annual free show, but she has been forced to cancel due to strep throat.

The X Factor judge is being replaced by country singer Hunter Hayes, who city officials say is “one of the biggest stars in country music right now.”

According to Entertainment Weekly, although organizers are disappointed Lovato won’t be able to make it, a mixture of local and national singers will be able to appear at the concert. Those on the lineup are The Roots, who call Philadelphia home, as well as John Mayer, Ne-Yo, J. Cole, Jill Scott, Grace Potter and Ben Taylor.

Lovato, 20, who recently laid her biological father Patrick Lovato to rest, let her Twitter followers know that she was feeling sick.

“I can't sleep cause my throat hurts!!! :(“ she wrote ahead of her canceled performance.

Digital Spy notes Lovato hasn’t made an official announcement about when she will resume performances as of yet.

image: NBC