Ditto S.G., its soy MILK to be wary of, because once its finally put into the soy milk package, its so overprocessed that its not even soy anymore but a big box of junk that contains nothing close to soy. I would never give my children soy milk, they've never tasted it and never will. They both ate tofu, however, as babies. Its a great soft finger food, when cut into small bits.
Tofu and soy in its original state is ok in small amounts, like S.G. said even Asian people eat soy in its original or very minimally processed state in small amounts.