My LO has always had an appetite and always cries for her milk when its due and was draining most of her bottles (4/5oz every 4 hours). In the past week, my LO just doesn't seem as interested. She still feeds every 4 hours but she isn't crying for it or 'rooting' for milk. She is also only having around 3ozs then won't take anymore. Why do you think this is?