I just tell you my experience. One day we discovered that a diaper is found under the pillow of the maid. The diaper is unfolded and seem have not been used. We did not ask the maid why there was a diaper under the pillow. We guessed that she might pour the milk into the diaper instead of feeding my daughter. (She feed my daughter in the bedroom with the door closed.) I was told that some may pour the milk outside the windows. They are so cunning, just be careful.