My childhood memories were just not about having or not having money. It was also about observing how others treated or pursued money.
Our house was not poor, but we managed. There was always food, even if it was not something I liked or wanted to eat. We only got presents at Christmas, and it was one, or maybe one and some small "stocking stuffer". No presents for birthdays, just a homemade cake.
My Dad would often say with a smile, if we asked for something, "Who do I look like? Rockefeller"? But if we really needed something, he managed to get it. My Mom was mostly a stay-at-home mom, but she did go to work if the family needed something major, as both she and my dad hated having "bad" debt.
They both learned enough to be handy people around the house and cars. My Dad got at least 10 years out of every car he owned. My mom knew how to repair things around the house, and taught all of her kids how to cook and sew.
With 7 kids, and me having older brothers, it was rare for me to get new clothes. We had lots of hand-me downs, and my clothes I passed down to my younger brothers. My sisters did the same. But my parents were keen to get clothes that would last well beyond a child growing out of them, and taught us how to take care of them, so we never felt ashamed of not getting new clothes.
All of those contributed to me and my siblings desire for independence. In addition... we lived for many years in a bad neighborhood , and saw up close and personal the results of bad decisions driven by a desire for money, a lack of money, getting into debt to others, or a desire to waste money. By the time I was 14 I was not a stranger to having seen street fights, murders, illegal gambling, robberies (and had been robbed myself several times), prostitution, drug sales and usage, drunkards, welfare, scams, etc. None of this struck me as "glamorous". I saw that, even if one had money, one could do a lot of stupid things with it.
So for me and my siblings, having money AND using it wisely became an important lesson from childhood. We did not think of it explicitly as "FI", but as having enough money to take care of our families and not be in debt to others or depend upon others". Which I guess is a major component of FI
.