My mom got run into by a trailer that was rolling down a hill. Luckily my mom decided she was a superhero that day and was able to push the trailer to the curb to stop it from rolling down any further (it was a pretty steep hill). She got away with only a broken ankle.
So I say yeah. Tell them.
My family had a trailer growing up and ours was stolen from in front of our house. It was never found.