Thank you for this one. I had a sister who suffered for her entire adult life. She had been diagnosed with schizophrenia and bipolar disorder, and your post reminded me that at there was at least one doctor who believed she suffered from DID. Most of my knowledge of such diagnosis came via my parents, and any talk of possible abuse was always avoided, so my guess, based on your description and my sister’s common tendencies, is that she certainly did suffer from DID. However, although I suspected that she experienced some sort of physical abuse as a child, I was never able to determine a truth in that. My father was very controlling and emotionally abusive, but my gut tells me he wasn’t physically or sexually abusive. However, my sister was doing a significant amount of drugs at a very young age. By the age of 15 she was, according to a family psychologist I spoke to years later, taking exceptionally high doses of LSD. He said he worked with many troubled teens over the years, but never saw anything quite like my sister. He recalled being woken one night by my sister banging in his front door (we lived in the same town) and when he greeted her she was absolutely convinced that the entire front yard was a sea of snakes and she was as terrified as anyone who believed such a hallucination. So, my question/comment is whether you think that heavy drug use, especially hallicinogenics, could cause trauma enough to induce DID. You mentioned that 5% experienced some other trauma, so this leads me to believe it is possible. At the same time, I also feel that physical abuse was probably likey. She passed away a few years ago, by what I can only describe as suicide by smoking. She was suicidal her entire life, but often takes about she how she knew she didn’t actually have the heart to do it. My mother is also at an age where she remembers very little from my childhood, so aside from the fact that she was quite defensive about any talk of abuse, nothing new is likely to come from her on that topic. I have been resigned for many years to never really know what happened to my sister. She was a tortured soul and just one of the many, many people who lead a very difficult life due to such conditions. Thanks again for writing this. I am always amazed at how beautiful and enjoyable your writing is. You have a real gift.