UGH. These tragedies are far too common. Fox News is killing people with their anti-science nonsense. 1,000 people a day are still dying of Covid in the US and almost all of those are preventable tragedies if only people would get vaccinated.
My niece is an ECMO nurse in Portland, OR and she had a case recently, husband and wife went to Vegas for the weekend. Came back with Covid. Wife was vaccinated, recuperated at home with a mild case. Husband was unvaccinated, 42, doing poorly on the ventilator but no ECMO machines were available because they were all being used already. Just too many tragedies.
Sounds like your son was very mature about the whole thing. I'm so sorry for your MIL - it must be especially awful to be a spouse who probably was trying to get him to get the vaccine, and then to experience this terrible loss.