An inert grenade was found in a passenger’s bag at Salt Lake City (SLC). It turns out that the passenger’s grandson had packed her bag. I’m sure you can imagine grandma’s surprise! Moral of the story: Do not let your grandson pack your bags! Another inert grenade was detected at Birmingham (BHM) and in this case, it was a gift for the passenger’s father. Read here and here why even inert grenades at the airport are a problem.
Source: TSA Blog