The late 'Soundgarden' singer and his band were scheduled to headline the festival in Columbus, Ohio on Friday.
The Duchess of Cambridge was still 'mom' during sister Pippa Middleton's wedding to James Matthews on Saturday.
The Princes were spotted outside of St. Mark's Church on the Englefield Estate in the English county of Berkshire for the nuptials on Saturday.
The Duchess of Cambridge helped her little sis every step of the way during Saturday's ceremony.
Kate Middleton's little sister tied the knot at St. Mark's Church on the Englefield Estate in England on Saturday.
The 31-year-old tied the knot on Saturday with both her niece and nephew adorably by her side.
ET traveled to the set of 'Outlander' in Scotland and challenged Sam Heughan and Caitriona Balfe to a secret-spilling game of 'Never Have I Ever'!
The Soundgarden and Audioslave frontman, who passed away on Wednesday, was scheduled to perform at the event.
The 2-year-old royal rarely left her mother's side.
The 35-year-old tennis star announced earlier this week that he will not be competing in the 2017 French Open.
Pippa married James Matthews in Englefield, England, on Saturday, six years after Kate tied the knot with Prince William.
The 3-year-old royal flashed a mischievous smile after serving as a pageboy.
Kate Middleton's little sister is officially off the market!
A source tells ET that Markle left Kensington Palace with Prince Harry on Saturday morning, but there was no sight of her at the ceremony.
