I have night terrors from being sexually abused and I have worked with survivors of sexual abuse and a majority of those that have been raped or sexually abused in one way or another that I have known and worked with have had night terrors so I can see why your therapist asked you that question. Its kind of standard for the therapist to check all avenues including the possibility of sexual abuse when trying to figure out where the night terrors are stemming from. its good therapist practice to ask that question because it shows they are leaving no stone unturned. what if a therapist didn't ask that question and later found out the clients night terrors was not from mania but from being sexually abused. that client could come back and sue that therapist for malpracitice for not bringing up the possibility of any form of abuse be it sexual, physical, or emotional as a cause for the client having night terrors. A good and ethical therapist checks all possible avenues BEFORE rendering a judgement as to where the clients problems are coming from.