DH and his family also had a tradition of indoor fireworks at family meals as did we, I can remember one which turned into a sort of weird writhing worm.
When H was in the Royal Free over Christmas and we wheeled him down to the cafe I was horrified to see his sister bring out a box of matches and an indoor firework with the intention of setting it off!
Can you imagine the effect on the fire alarms , smoke alarms and sprinklers and trying to evacuate a huge 12 storey teaching hospital with some very very sick patients? That would surely have got top billing on my Christmas disasters thread! ????