Shush it!

I'm working at my computer.  Chris is yelling about his computer game not loading.  Patience is not his forte right now. 

Me:  Chris, shush!
Chris:  Shit!
Me:  What did you say?
Chris:  Shit.
Me:  Don't say that.  It's not a nice word.
Chris:  Why?
Me:  It's a not nice word for poop.
Chris:  But Mommy, you always tell me to "Shush shit"
Me:  That's Shush...  It...
Chris:  Oh.