Our cat has gone missing 
(it's been over a week now).
Even worse is the children are due here at weekend and they absolutely adore him and will be gutted. There will be lots of tears I know.
My husband doesn't want to tell them and instead thinks we should lie and say we've rehomed him somewhere like a farm with fields etc...
I think we should tell them the truth.
Firstly because they'll question why we've given their cat away and we'll be the terrible ones. And secondly, because I think they are old enough to know that sometimes these things happen and it's rubbish and sad but we shouldn't hide it from them either. They are 9&11.
And thirdly of course, he still might come back!!
YABU - lie to save them the upset of thinking he's ran away/something bad might have happened.
YANBU - tell them the truth, they are old enough to know. Which is that he is missing and we are trying to find him but that might not be possible.