Dave Grohl's daughter Violet sang with his fellow Nirvana band members on Thursday, Jan. 30 at the FireAid Benefit Concert for California Fire Relief

Violet Grohl surprised fans by joining her dad and the surviving members of Nirvana on stage at the FireAid Los Angeles Benefit Concert on Thursday night

The Grammy Award-winning band shared that they had to pull out of two shows due to a 'critical illness' in the family.

Dave Matthews will be sitting out the FireAid and MusiCares benefit concerts due to a 'critical illness in the family.'

CNN has reached out to a representative for Matthews for comment. The FireAid benefit concert, a music event set up to aid the relief efforts following the deadly and devastating Los Angeles wildfires, is set to take place on Thursday at the Kia Forum and the new Intuit Dome, both located in the LA city of Inglewood.