The Herald Sun is reporting that the two are heading for Australia for their wedding, which sources say is taking place Sunday, June 25, in Sydney. Neither star has confirmed that report, however. The Herald Sun says that the two boarded Nicole’s private jet from Nashville June 15 en route to Shanghai, where they will spend a few nights before heading to Australia to celebrate Nicole’s 39th birthday. After that, Keith and Nicole will reportedly tie the knot, at Mary MacKillop Catholic Church in Sydney. Rumored to be among the wedding guests are actors Naomi Watts, Russell Crowe and Hugh Jackman.