This forever always A+ list singer/celebrity has been undergoing tests because those close to him fear he has the beginning stages of Alzheimers. Our singer/celebrity is not that old, but has been forgetting lyrics and repeats himself constantly and has been snapping at his kids and partner almost non-stop.
Source:
http://www.crazydaysandnights.net/2013/08/blind-item-5_5.html