My sister supervises my mother. I think she's herself supervised by one of our aunts, but I rarely if ever see them together, for unrelated reasons. My mother's friendship with that aunt kind of reminds me with my own friendship with SEI, so super-ego probably makes sense. (Side-note: if she's LIE, I think this type should never, ever focus on their health. Or at least, destruction of the body in the name of health seems like a Si fail to me.)
No supervision for me in close family.
I'd take it over conflict any day.