As my parents would only take a thermos of coffee in the car on road trips (short or long) all 3 of us were rather forced to learn to drink it at an early age, and black at that. Neither parent could abide white, sweet coffee.
I remember learning to drink coffee at all when I was about 6. Dad had taken some scouts to an areak skeet shoot and the concession stand had only coffee as a hot drink. I wanted hot chocolate but no joy. The stand person put lots of milk and sugar in the coffee.....and I was on my way. Drank it white and sweet for about a year, then weaned myself off and on to plain black so I could have some of what was in the grownups thermos bottle!