History ?
Has he got a history of sleep disorder?
If he has not - he is in trouble.
I have a history of doing stuff while asleep.
I have tried to drive cars & go to work (on a Saturday !!!).
I also fly Harrier jets, win the US Open (Golf) you want to see my celebrations!!! and I ski off cliffs. Well 2 feet off a bed.
My ex-wife said it was like watching a soap opera with me talking with my mother (who died 8 years ago).
We laugh about it but it happens.