I have felt concern for a Grandchild who had to be transferred to soy milk in early infancy because of intolerance to regular formula. Some believe that natural hormones in soy might effect children in some way later on. I actually asked her pediatrician about it and of course, she comforted me but she doesn't know. So many substances are put into our food, most in an attempt to make us healthier, but even too many vitamins or minerals might effect children. When my brother was an infant, my Mother refused to breast feed him because the belief was that "cow's milk" caused children to be taller adults. My view of child obesity is that children do not get enough exercise because of lifestyle changes and parental fear of letting them roam around without adult supervision..Computers and video games along with little space at home to play ball, ride bikes, etc., has an impact.
I think that is why I perked up when she made the comment about soy, when I posted the question I completely fogged out that you had mentioned it. Please forgive the brain fog.
I have heard that children who were raised on soy milk tend to have weaker immune systems. Somehow this is related to the presence of compounds in soy that are similar to estrogen. On the other hand someone I know has a baby who was transferred to soy milk and he seems very healthy.