I had one exactly like this. From day one I suspected it was related to milk...she drank 2 8 ounce bottles per day, and it was always after she drank milk that she pooped. Eventually I suggested to the parents that we cut down on her milk to one bottle per day since I thought it might be interfering with eating ( she's a picky eater)...it has improved soooo much. We are down to 1-2 poops per day now, and her diaper rashes are much less frequent. I find that parents just give way too much milk sometimes... I never did because my kids were allergic, and they are great eaters, those who fill up on milk all day however are always the picky eaters...