Sounds like your sister is moving in the right direction! Take things slowly and carefully with her. She has to figure things out for herself. Ask her where in the bible people got publicly reproved. They reprove her without telling the congregation why, which leads to vicious and slanderous rumors that poisons everything. In Isrealite times they carried out a public hearing to see if the accused was guilty of a grave sin or not. Nothing like what they do today.
By the way, I LOVE your avatar! I'm an avid lepidopterist and very involved in conservation projects locally to protect endangered butterfly species.