An actual example.
Some twenty minutes from our destination, our home base, the captain slumped over, unconscious. He was a large man and never wore the full harness en route. Fortunately he did not slump forward on to the yoke.
I called the FA who managed to get him upright and secure him with the shoulder harness while administering first aid. It would have been impossible and highly dangerous to have attempted to move him.
Although there were a couple of closer airports, in view of the weather and the higher workload that would have been required, I elected to continue to our destination.
The FA was invaluable as she contacted the company on frequency, advised them of the situation and arranged for paramedics and an ambulance to meet us.
For checklist I used the essential memory items and we landed without incident.
Happy ending was that the skipper made a full recovery.