Hi guys. At 12 months , I switched my DS from formula to cows milk...as you do....and found that it upset him...tummy ache, runs or constipation....visited GP who told me to switch back to formula and to try him again at 2 monthly intervals...he is now nearly 2 and still has the same reaction to it...although he is ok with yoghurts and cheese, its just when he starts having substantial amounts he becomes uncomfortable. NOW..my GP is telling me that my DS's problem is an idiosynchrasy, he CANT have a problem with it as his formula is based on cows milk...and the yogs and cheese blah blah....but the minute I switch him, he gets uncomfortable again!!! What shall I do? The GP also told me not to use soya as I will be compromising on vitamins, and to try semi-skimmed milk (which I thought you shouldn't do with kids???)....HELP!