Powerful Saudi royal heirs will define kingdom's future

Crown Prince Mohammed bin Nayef, 56, and Deputy Crown Prince Mohammed bin Salman, 30, are next in line to succeed 79-year-old King Salman in ruling the world's top oil exporter, as it faces regional turmoil and low crude oil prices. People who have attended meetings between the two cousins describe their public interactions as cordial and respectful, but such accounts have done little to stem suspicions among some Saudis that this apparently amicable facade hides a more fractious relationship. T