soymilk is not suitable as an infant formula because it doesn't have all of the right components to be complete for a baby, not enough fat etc. there are soy infant formulas that have the fat etc added so those are what are used fir formula. i personally go on the diversified idea that i use soy, but not as my relacement for everything, i rotate so that my body doesn't develop an aversion or the hormone thing doesn't become an issue. I only eat tofu 2-3 times a week max and rotate between rice and almond milk as i don't like the taste of soy milk, i also avoid products with all of the processed versions of soy as they are almost always GMO. i would say go ahead and give your kids the soymilk, it is much better for them than regular antibiotic laden milk and less allergenic, but also try other alternative milks so thats its not always soy.