One must make allowances for a parental instinct that has been starving for twenty-five or thirty years. It is famished, it is crazed with hunger by that time, and will be entirely satisfied with anything that comes handy; its taste is atrophied, it can't tell mud cat from shad. A devil born to a young couple is measurably recognizable by them as a devil before long, but a devil adopted by an old couple is an angel to them, and remains so, through thick and thin.
Mark Twain, Pudd'nhead Wilson
parenting