My life has been quite a story..My dad says I was very ESFJ/P-like (LOL) up until I was about 5. My mother died when I was 3, and I moved a few times afterwards, and when I was 5 we finally settled down again. Because of all that was going on (environmental stimuli) I changed drastically until I was about 7. I was more quiet, and way more layed back. I'm think I was more ISFP-like. Life went on, and about 4 years ago, my father remarried. Last MarchShe ended up cheating on him, and moved out within a month, and it royally screwed up our family. I gained self awareness, and started thinking differently. My dad is extremely firmiliar with the MBTI and through him, and several tests, I started to shed the skins of who I thought I was, and became who I really am.
I don't mean to ramble on, but my point is that if drastic change is brought about, especially in times where a peson is most vulnerable (when I growing up), that it can the person. One could argue that types don't change that easily, but types are simply gerneralities, and are by no means set in stone. This may not be exactly related to the topic, but I feel it demonstrates the INFPs nature.