I heard he had leukemia. That wouldn't make him critical though. They can treat that these days can't they? Mind you, there's been rumours about his health for the last year or so. I'm not a big fan but I hope he gets well.
He was the first international pop star from rural ireland, a great entertainer, there was no show like a joe show.
I think he once blamed Elvis's death and the dleuge of re-released elvis songs hitting the charts for his own comeback to the international charts failing. I remember him on Top of the Pops at the time. He brought a smile to the face.