She said what?

Once in awhile I hear a "really bad" word come out of my 3 yr old. You know, the kind of word that you really take notice of all the way from the other end of the house?  She called her big sister a fxxxing bxxxx!?!? Of course, she didn't come up with it on her own--she stole it from her foul mouthed, teenage brothers.

The rule in our home is: We don't use foul language in everyday conversation. With the exception of saying "FXXX" when you drop an anvil on your toe. Only then is it warranted.

I'm pretty sure that, that rule is common in most homes. However, when I was a kid there were only a few "bad" words that you "weren't supposed to say". The line between good and bad, back then, was pretty simple to follow. Evidentally not so much these days.  So now what do you do when your 3 year old says, "pervert", or "homo"...?

NEW rule: If it wouldn't sound right coming out of the mouth of a 3 year old, DON'T SAY IT!