I’m thinking it’s the sad situation where the teenaged girl is ‘blinded by love’, and runs off with a creep, who killed her family. It’s even possible she helped him kill her mother and brother. Horrible to contemplate, but sadly, it wouldn’t be the first time it’s happened.
Look up Charlie Starkweather. He got the electric chair and his girlfriend got a few decades in prison. All the local folks thought they should save some money and put her in Charlie’s lap then light ‘em both up at once. They could ride the same bolt of lightening.