Verified answer

uhmmm, most certainly NOT

Thank you for the laugh! Chuckles! As far as I know there is no weird phenomenon that happens when you combine the two. Though I have yet to try it myself. Unfortunately I do not have soy milk to test this theory out. ;-) …so I will give it a try with Rice Milk and Cows milk and see what happens…

I think your brother may be adding more than soy and regular milk to that drink. He may see the occurrences, but they are not caused by milk!

Maybe the soymilk was made from genetically modified soybean, and the cow's milk came from cows that were injected with rBGH?