Okay, catherine's violin didn't exactly explode but it did make a loud noise as the bridge shot out and the strings collapsed. Catherine looked at me and I looked at her and we both cursed (again) the cheap violin I'd bought her.
Lessons were today so we packed up the violin and bridge and saved them for the instructor. Got there, has a great talk (sorted out all my previous concerns with her- basically I was panicking for nothing) and then she put the bridge back in. Catherine played for five minutes and then... *CRACK* the bridge broke in two and dropped onto the floor. The teacher was more then a little frustrated at this point. She confiscated it so the music shop owner could have a look at it and see if it could be fixed or there's was something defective about the body and construction.
The lesson - If you're going to buy a violin, do your homework and open your pocketbook. Cheap violins are hard to keep tuned, awkward to use and prone to failure.