Did you drink well or city water as a child? The fluoride in the water could be a factor as well.
In a family with radically diverse genetics, and radically diverse oral health outcomes seemingly independent of oral care: congratulations on hitting the genetic lottery!
We just drink soda water.
Sure but do you get it in a can/bottle or make it yourself? The latter done with public tap water would still contain fluoride.
My kids have no cavities / perfect teeth. My wife and I, by that age range, had tons of cavities.