The last time I accepted the free vacation, my level 10 scientist came back unemployed. Now she has to work her way all the way back up to the top. Although, that is partially my fault, seeing as I stupidly deleted the save I had made before they left.
But to prevent stuff like this happening in the future, I'd recommend doing Save As and creating a new file every single time you save, rather than just hitting Save and making the file bigger. It helps tremendously with issues like Error Code 12 (when the file is too big to save it), and when your game inevitably goes corrupt one way or another, you'll have backups.
The way I do it is I count up with every save. For example, my current game is called Bernadette, so whenever I save I save it as Bernadette1/Bernadette2/Bernadette3/etc. I'm almost at Bernadette200 and I haven't had an issue with Error Code 12 at all. But, obviously, you don't want your main menu all crowded up with a million different copies of the same game, so when deleting old saves I'd recommend that you keep at least two or three versions of your family. It might be kind of annoying to remember to do at first, but it really is worth it to keep your precious Sim families safe.