yes, the boy in Van San't screen play is a prime candidate for trauma-induced multiple personality disorder or DID as you put (Dissociative Identity Disorder) , which is the same thing. His mother was a stripper and mental patient with a seizure disorder herself, who abandoned him to be raised by his brother while she was under hospital care , so he was raised by his older brother who is possibly really also his father. as the dialogue implies. (so he's possibly the product of incest) and there are snippets of video where his mother has him dressed in pink girls' clothes as a baby and drops him on the ground when she has a convulsion ...etc.)

So the subplot is that the baby was taken away from her, and that the main character Mike Waters may been some sort of satanic cult-abuse victim from the day that he was born. Hence the multiple personality disorder, where he has 'missing time' after dissociating into alter personality. Presumably those are gender-dissociative identities as well, because his narcoleptic attacks often happen when he's about to have sex, and he is hypnotized at one point by a 'handler' who later transports him to Europe. Bear in mind that in the screenplay this was all done on a 12 yr. old. What no one will tell you in this movie is that in real life there is a huge gender-dissociative component to the street 'rent boy' scene. IF you watch Cops you will see the scenes of trannies constantly being busted by police for either posing as female hookers and getting themselves in trouble, or for working the gay hooker strolls in various cities. Every city has one, an area where men can find gay street prostitution. For some reason all of this was censored out of the film. But the real life 'Mike Parker' is clearly a gender bender type, its easy to imagine him having worked the stroll in drag, with his full lips and slight build etc. lending themselves well to the transformation. My Own Private Idaho only 'hints' at it....such as the scene where Mike Waters is dressed as a maid and forced to clean the kitchen for a rich man who clearly gets off on feminizing him into a subservient gender-dissociative role. All of this presumably when , according to the original screenplay, the young boy is at a crucial time of developing his own sexual maturation and identity (puberty). So the subplot to the whole film is that Mike Waters is gradually turned into a woman , for all intents and purposes, and by the end he is on his own, completely degraded and then abandoned by the people who created him. My suspicion is that Gus Van Sant's original director's cut was heavily edited by the production studio before it was released. Probably to remove the references to gender-dissociation to make it at least a bit more palatable to the general public than it originally was. In fact if they cut as much as I suspect they did, it may have even required a reshoot, to restore it to Hollywood production lenghth. Van Sant hints at this sort of thing in his later film 'Jerry' , which features a full four minutes straight of two men trudging side by side through mud. As though VAn Sant is making a private joke about how he had to use 'filler' to lengthen the film after they cut it to pieces. I suspect that there is a lot of 'filler' added to My Own Private Idaho for the same reason, but to find it I would have to go back and watch it again. I don't ever want to see it again, truthfully. It is depressing. Possible 'filler' is the silly scene where they have REaves woodenly reciting lines scripted for them and intentionally botched as an amateurish school play, etc. Probably another one of Van Sant's 'protest' gestures to the producers who had restricted his freedom and forced him to cut , reshoot and lengthen the film. It was like 'ok , if you want to cut my work to hell, fuck you then. The reshoot version of this is going to be BAD, don't expect me to help out much on this' etc. So Van Sant punishes his financiers by delivering them a ham-fisted reshoot