Should DSis visit

[DirectionsForUse]

DH is seriously ill and my sister would like to visit this weekend. She lives approx 3 hours away and would usually stay at our parents who live nearby. She plans to come alone leaving her DC with her DH.

Her DS1 has been told he needs to isolate due to contact he had on Friday, So it will be 8 days by the time of her visit.

So far he has no symptoms and Lateral Flow tests are negative.

She (and her son) would take a LF test before she leaves. I and parents are fully vaccinated, DH and DSis have had one vaccination.

So by the letter of the rules she can come, as unless DS gets symptoms only he is isolating. But should she? Would you?

DH is unconcerned, the way he sees it he's dying anyway, but not so close that this is her last chance to see him.

By day 8 as a contact of a possible contact then I would be comfy BUT if either of you aren’t comfy then I would say no.

It's my parents I'm most concerned about

But their vaccinations really should mean there's no need for concern.

So there's a chance that DS1 could be infected. If so then a chance that he could pass it on to your sister. A chance that BOTH could test -ve still prior to the visit. A chance that your sister could give it to your parents, who are protected by vaccination, so the chance that they could die has been reduced to a chance of a chance.

Heck I'm ultra cautious, but no hesitation here. As long as you trust your sister with LF tests, i.e. she'd cancel if either her or her husband came up +ve.

Otherwise, by the time you've multiplied together all the risk coefficients, you probably end up with something lower probability than a lightning strike.