Fried Chicken and Sushi 191 Sato sensei's husband's family?

I remember when this one really happened.  Actually, it was more like I couldn't remember the English word for in-laws at all!  It was totally embarrassing!  All of the teachers were so disappointed that I couldn't remember such a simple word in English.  I had to go online and search for a word in my own language!  It's pretty easy to forget certain English words while living in Japan because you never use them or hear them around you.  Anyone out there have a similar situation that made them look like the incompetent native English speaker?