Research so far: I've googled Victorian corsets, corset training, and the like but seem to get only contemporary/modern sites for the latter, and history of corsets or corset makers for the former. I looked on the Victorian Web but wasn't able to find anything on this there either.
I'm looking for the approximate age a girl would begin wearing a corset, or training her body/carriage to handle one. My character is a 15-year old aristo girl with a very strict aunt so they would have gone by the book of rules for the era. Somewhere online I once read that they started children as young as toddlers in corset training; I didn't bookmark the site and now can no longer find it or determine whether it was a legitimate claim. Any help in the matter would be greatly appreciated, thank you.