Hey there! I'm new around here and thrilled to be surrounded by fellow typology nerds. (For random reference, I'm not revealing my type yet. It's fun for people to guess.)
Anyways. I'd like to know when the functions actually develop, and if they're evident before reaching full development. I heard the first function develops in elementary school, the second in adolescence, the third in young adulthood, and the last around middle age. Can functions be more developed even earlier in life? I will use a personal example.
My dominant and auxiliary were both very well-developed even in elementary school. Though I used them equally, they tended to shift slightly each year, one becoming a bit more dominant than the other. This would affect the way I acted and presented myself during said year.
Another example is my sister. I'm pretty sure she's an ISTP, but her tertiary Ni seems off the charts for someone of her age.
Also, can functions develop out of order? My tertiary function is actually my weakest of all; I utilize functions not even in my stacking better than my tertiary. I'm really an ambivert, so that might affect the order of my 3rd/4th function.
What do you think? When, in your opinion, do the functions develop? Does ambiversion affect the order of tertiary and inferior?