John Easterling and Olivia Newton-John
07/10/2008 AT 01:20 PM EDT
Olivia Newton-John married natural-health businessman John Easterling in two secret ceremonies, her rep tells PEOPLE exclusively.
Only the bride and groom attended the Incan spiritual ceremony held on a mountaintop outside of Peru on June 21. The couple then returned to the U.S. and made their union legal with a beachfront wedding in Florida's Jupiter Island on June 30.
The newlyweds kept their nuptials hush-hush until a 4th of July barbeque held at the singer's Malibu home, where Newton-John, 59, surprised their guests with the good news.
Newton-John and Easterling, 56, founder of the Jupiter, Fla.-based Amazon Herb Company, met through a friend more than 15 years ago but only became romantically involved last year.
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