Another cause of infantile indigestion, and which is too much overlooked through ignorance of its importance, is _vitiation of the quality of the milk_, caused by imprudence, neglect, or anxiety, on the part of the mother. The extent to which this cause operates in inducing irritation and suffering in the child is not generally understood; and accordingly, it is not unusual for mothers to display as much indifference to health, regimen, and tranquillity of mind, during nursing, as if the milky secretion, and all other bodily functions, were independent of every external and corporeal influence. Healthy, nourishing, and digestible milk, can proceed only from a healthy and well constituted parent; and it is against nature to expect that, if the mother impairs her health and digestion by improper diet, neglect of exercise, impure air, or unruly passions, she can nevertheless provide a wholesome and uncontaminated fluid, as if she were exemplary in her observance of all the laws of health. It is no new or uncertain doctrine that the quality of the mother’s milk is affected by her own health and conduct, and that, in its turn, it directly affects the health of the nursling. Even medicines given to the parent act upon the child through the medium of the milk; and a sudden fit of anger, or other violent mental emotion, has not unfrequently been observed to change the quality of the fluid, so much as to produce purging and gripes in the child. Care and anxiety, in like manner, exert a most pernicious influence, and not only diminish the quantity but vitiate the quality of the milk. As soon, then, may we expect to see a bad tree bringing forth good fruit, as bad management good results; and low must that parent be ranked in the scale of moral beings, who, knowing the relation we have pointed out, can still deliberately sacrifice the welfare of her offspring, by the improper indulgence of her appetites and passions, and by culpably neglecting the duties and restrictions demanded by her own health.