I don't know. She is not exactly the standard ISFJ though. Her Te is almost as strong as her Fe, and seems to act as the relief role instead of Ti. Both Ti and Se came up as Unused.
Her personality might be influenced by her Bipolar and OCD, as well as by the medications for those. I used to think that she was naturally an INFJ whose personality had been changed by the medication, but thinking back to some tapes we made when we were kids I think Si was probably stronger than Ni then too. I do tend to think that her intuition and introverted thinking may have been weakened by the meds though. (Well, I suppose you could say both types of intuition were greatly strengthened during those 2 real manic episodes years ago when she went for days speaking almost nonstop in rather rapid rhymes, but that is far from common.) When she was young she used to love staying up reading, but since being put on lithium (and a couple other things at the same time, I'm not really sure which might be responsible) she has to reread the same passage several times to have a clue what it meant and is often put to sleep by books that would once has fascinated her. She is no where near as bad about that now as she was a year or two ago though, as her dosages have been reduced since then.
Saying that she confuses a week ago with a decade ago was hyperbole, but she definitely does have trouble putting events from several months and several years ago in order. She acts amazed when I describe memories in a set timelines including dates from years ago, claiming that she requires context clues like whose classes she was taking at the time to help her out. She also forgot about my grandfather's death about 3 weeks after it happened, which made it hit hard again once she remembered.