10 years ago, when Rory was just 15, his father Gerry McIlroy placed a £200 pound wager that his son would win the British Open before his 26th birthday. At the time, Rory was a teenage golf prodigy who was still three years away from turning professional. Three of Gerry's friends went in on the wager, bringing the total bet up £400 pounds (roughly $683 USD). The bet was so far fetched that the bookie who took the other side gave it the biggest odds allowable at the establishment.
http://www.celebritynetworth.com/articles/celebrity/10-years-ago-rory-mcilroys-dad-placed-100-bet-son-win-british-open-turned-26/
http://www.celebritynetworth.com/articles/celebrity/10-years-ago-rory-mcilroys-dad-placed-100-bet-son-win-british-open-turned-26/