So sad really. I suppose all they wanted was to stay warm.
It's sad and also so easy to happen.
Many years ago, I was in an incident with CO that could very easily have turned very bad.
5 of us were involved, very early on, one said they had a headache and went off to bed (presumably she was the most sensitive to the fumes or just lucky)
Fortunately I realised that I was becoming lethargic and having problems concentrating, the others were either already asleep or in the same state.
Fortunately I guessed what it was and quickly opened the doors and windows and called emergency services.
Two were elderly and were badly effected 4 taken to hospital (3 because they needed it and one because she was a ******* drama queen although had been the least exposed)
After some oxygen from the paramedics and as I had been very active getting fresh air into the room I was fine and was able to drive to the hospital later to collect them.
(also going over the incident later I also realised that I was sitting nearest the door into the room so because of the draught was possibly getting a slightly lower concentration of CO)
Cause ? a woodburner with a dirty flue that the elderly owner, in her wisdom had fed with coke .... sigh !!!
Could easily have been very nasty, when it is happening it can creep up on you and if you are unfortunate, you won't realise in time to do something about it.