So the In-laws have made it home ok. SiL and niece had a horrible trip. Not sure if it was the stress of travelling or if they had some bad food along the way. Everyone else is ok, and they are all home now.
There was also an unfun moment when my BiL realized he gave the wrong date to the person picking them up from the airport. By the time he got ahold of the friend, they had been at the airport for two hours, a day early. Since they got home ok, I guess the friend came back on the correct day.
My wife is handling the suddenly empty house. She is very sad they are gone but able to function. She gets particularly choked up if our son goes into the rooms everyone was using and starts looking around like he lost something. It does not help that one of his favorite sounds these days is "Ba ba ba" which can be taken to be the Polish word for "grandmother" > "babcha". (ok, so we have also been taking it to be "ball" but that does not make sense in this context. And it is all about context.) So it will be a while before she gets her feet planted again. She has been focused on this visit for so long I am curious, in a dreading/morbid kind of way, what she will start doing with her time. She did get out a book from the library last night, which I take as a good sign she might take some time for herself. I can only hope.