My Kentucky grandmother would have said "Lawd ah mercy." "Growed" was what her granbabies did. As in, "I swan chile, you'r gettin biggah ever day."
She never showed much inclination to violence except when it was time for a chicken dinner. I still remember being amazed at the chickens running with their heads cut off. My grand dad just worked the farm. By the end of the day, he was too tired to indulge in any possible violent proclivities.
I think the study was apocryphal. Just some Northerners who still haven't gotten over the War between the States.