There is a reason it is ilegal (at least in Spain) to have campings in historically active ravines. This happened after the much similar incident in Biescas almost 30 years ago.
Sorry but you can't depend on forecasting for everything. The earth has showed us again and again that if it gets the shits you better not be in the way.
Pre-teen is the worst age for this. Just try to get your kid past this the best you can. Happens everywhere, eventually they will mature and learn.
Heck, this is always the plot in school movies.