I don't know if this will be helpful, but I have a first hand experience on this. I was INFP as a child. My ESTJ mother's persistent influence turned me into an INFJ by the time I was a teenager, but today, I would think it's fair to say I'm in between J and P, trying to make the best of each preference.
When I was 9 (and still pretty INFP), my ISTJ brother married an ISFP. She is a virtuose pianist and became my new piano teacher. I was all in awe about her, full of respect and admiration. She was very kind to me and took me places sometimes (bike rides, movies, shopping). I was surprised at how well we communicated and understood things in a similar way. We got along quite well musically speaking, both having an intuitive way about hearing and remembering music, creating back vocals and so on. We shared the same odd, dreamy and imaginative childhood experiences. We loved the same books.
Very often, when I felt the need to share something personal and meaningful that my ESTJ mother would never understand (or care to understand) I would go to her, and she was pretty receptive.
My sister-in-law cries all the times when she watches a movie. It rarely happens to me (the movie has to touch me very deeply) but it happened once when I saw a tv-movie about Joan of Arc (Joan of Arc is an INFP archetype). I shared my feelings with her about it (she had watched it as well) and admitted she was quite indifferent to it. Joan's spiritual passion meant nothing to her. That is one of the events that made me understand our difference.
Also, I was often surprised at how adventurous she was, always trying new things, while I prefered to trust the things I loved and knew well. I noticed how, even as a good Christian, she did things that seemed borderline immoral/illegal to me, without seeing anything wrong in it.