The allegation that Tawni may have been molested by her step father or someone else in her family is going to be really hard to prove, IMO. Unfortunately since they believe she was prostituting, any genital/pelvic injury could mimic sexual abuse. If she sustained no pelvic injury from being abused sexually it's going to be even harder to prove. But if she did endure sexual abuse from her step father, or any type of abuse for that matter, I hope he does get called out on it and evidence points to him, and he does rot in a prison cell for the rest of his life.
Yes, a lot of Tawni's characteristics from what we know so far are compatiable with those of a sexually abused victim, but a lot of those characteristcs are also common in emotionally unstable people. I have depression and anxiety and when I didn't take my Effexor/Klonopin when I was younger, I could, and still can get pretty downright defiant, aggressive and unreasonable. Personality disorders and especially not having a positive male example can also cause promuscuity, and I'm not trying to say Tawni was, but some individuals can interpret sexual acts as love. Just throwing that out there since there has been no mention from the family that Tawni was sexually abused. If she was sexually abused though, wouldn't she want to make herself less attractive? She was pretty meticulous about her grooming and appearance.