I would bet the 19 year old was undergoing the same abuse and had escaped. If that is the case, I don't think she should be prosecuted if found.
“Claiborne County Sheriff’s Capt. Sam Nelson, who investigated the case, testified that he told the older girl that she could go to prison if she had been witness to the events while she was an adult.”
I’m guessing here...
But I suppose the 19 y/o was also a victim and was also threatened by him. If so, this captian spoke reckelssly. Even at 19 the daughter may have still suffered under the father’s horrors. Heck, his threats may have included the “if you know whats good for you and your sister, you’ll shut up.
Prayers for these poor girls.
The mother and the monster can both rot in hell.