Tim Roll-Pickering has sent me a text in the past five minutes to say that David Cameron's eldest son has died. This was swiftly followed by a newsflash from Sky.
I am shocked. I know he had cerebal palsy, but many sufferers have been known to live with it for many years.
Thoughts and prayers go to the Cameron family during what must be an anguishing and desperate time!
UPDATE: I now understand that Ivan Cameron had severe epilepsy as well as cerebal palsy, which is quite rare. My apologies for getting it wrong earlier