This is for my NaNoWriMo story from last year that I am planning to rewrite this November. The first time I used lung cancer because it seemed ideal for the purposes - had the character coughing a lot, losing weight, etc, - but I'm thinking that the end stages would be far too painful for my purposes. I'm having a hard time finding any information that isn't either candy-coated for the purposes of patients or mostly for preventative purposes.
I've also tried to do some research on perinatally-transmitted HIV/AIDS, but I'm getting the impression that the death would be too soon (the average age of death is eight or nine). I would like the character to be mid-late teens, which is too late for this and too early for him to have gotten it transmitted sexually, since I'm under the impression that the estimated life expectancy after being diagnosed is 10-11 years (which would mean he'd have to be having sex at a very young age and I'm not sure if I'm comfortable dealing with that in the story). And, again, I'm having a difficult time wading through the preventative advice and finding information about what it's actually like, and what it would look like from the outside.
This is more of a "could it happen?" question than anything. In the original version of this story, I have my main character (who's point-of-view it is from) taking over / taken over by the identity of her older sister. This sister was the 'family favourite' and died traumatically (in the original she was hit by a car). While the family is grieving, the character gives her name as that of the dead sister's, starts to wear her clothes, and slowly begins behaving the way she did. Is there a name for this sort of thing, so I can look for more information and make it work better? Would it be considered Disassociative Identity Disorder? Does anyone know of any cases like this I can look up?
I've plugged various phrases into Google and Wikipedia and found nothing like what I'm looking for.
Thanks in advance for any help you can give me!