INDIANAPOLIS (AP) _ Singer Olivia Newton-John and her race driver nephew have signed up to take part in the annual 500 Festival Mini-Marathon in Indianapolis.

But Newton-John and Firestone Indy Lights series driver Emerson Newton-John won't be running in the 13.1-mile race on May 3, they'll be walking.

The aunt-nephew duo will lead a “walk within the Mini'' to promote their cancer awareness campaign called Pink and Blue For Two that focuses on breast and prostate cancers. They're inviting others to walk with them to support that cause.

Emerson Newton-John is co-founder of the campaign and his aunt, who's a breast cancer survivor, is the ambassador.

He tells The Indianapolis Star that getting the Pink and Blue campaign to become part of the Mini-Marathon “is bigger than we ever hoped for.''