There were a litany of issues that reared their heads in the lead up to Bill and Melinda Gates’ divorce after 27 years of marriage. Throughout their decades together, the billionaire couple reportedly had a "combo of things " that prompted the split and the fact that their youngest child, Phoebe, is now an adult – the Gateses -- Bill, 65, and Melinda, 56 -- simply felt now was the right time to end things for good, a source told People magazine on Friday.