I'm feeling quite 'lost' at the moment. My SD who I've always struggled with due to concerns over her emotional state and tendency to be aggressive as soon as her father disappears out of the room.I have closely observed her relationship with her younger half siblings, baby and toddler. The interactions appear 'normal' enough when everyone is around but recently when our backs are turned she has been pushing and hitting my toddler. I also became aware of other disturbing behaviours which show she is internalising a lot of aggression. She demonstrated that she is experiencing an internal struggle between wanting to 'protect' her siblings from being hurt and wanting to hurt them... needless to say when she visits during holidays I sleep very little as I am gravely concerned as to what's going through her head since she often puts on a very inauthentic positive facade.. I feel she needs psychiatric evaluation and support.. but this will be a long drawn out process. In the meantime, I am at a loss what to do about future visits etc and how I can support my husband but also keep my two little ones 'safe' when I'm out of sight... I don't feel that her behaviour is purely triggered by divorce/separation/craving father-daughter time although this would certainly be a contributor, I feel that her behaviour stems from much deeper seated issues.. please help