I would hang on to those which would be sent to their close family. Last posting dates are some way off yet. If things don't go well for him you could have a rethink.
he was driving his mobility scooter and got hit by a hit and run driver, he is in hospital with 5 fractures to his spine and multiple other injuries. The family go
up and see him of course, but it doesn't look good.
"SIL's brother". Does that not make him your brother in law, Emmie.
You say he may not make it but he could hang on in there for some time before giving up the fight. I'd probably still send the card.
You don't need to post cards for the UK for another 2 weeks at least...wait and see how things progress. If you are still not sure there are plenty of cards with a suitable picture and virtually nothing written in them which may be more suitable.....
Personally, I’d wait Emmie,my friends son committed suicide a couple of years ago and I didn’t send a card for the first Christmas, it felt not right somehow