Fyodor Dostoyevsky said this quote

“ But I've still better things about children. I've collected a great, great deal about Russian children, Alyosha. There was a little girl of five who was hated by her father and mother, 'most worthy and respectable people, of good education and breeding.' You see, I must repeat again, it is a peculiar characteristic of many people, this love of torturing children, and children only. To all other types of humanity these torturers behave mildly and benevolently, like cultivated and humane Europeans; but they are very fond of tormenting children, even fond of children themselves in that sense. it's just their defencelessness that tempts the tormentor, just the angelic confidence of the child who has no refuge and no appeal, that sets his vile blood on fire. In every man, of course, a demon lies hidden- the demon of rage, the demon of lustful heat at the screams of the tortured victim, the demon of lawlessness let off the chain, the demon of diseases that follow on vice, gout, kidney disease, and so on.This poor child of five was subjected to every possible torture by those cultivated parents. They beat her, thrashed her, kicked her for no reason till her body was one bruise. Then, they went to greater refinements of cruelty- shut her up all night in the cold and frost in a privy, and because she didn't ask to be taken up at night (as though a child of five sleeping its angelic, sound sleep could be trained to wake and ask), they smeared her face and filled her mouth with excrement, and it was her mother, her mother did this. And that mother could sleep, hearing the poor child's groans! Can you understand why a little creature, who can't even understand what's done to her, should beat her little aching heart with her tiny fist in the dark and the cold, and weep her meek unresentful tears to dear, kind God to protect her? Do you understand that, friend and brother, you pious and humble novice? Do you understand why this infamy must be and is permitted? Without it, I am told, man could not have existed on earth, for he could not have known good and evil. Why should he know that diabolical good and evil when it costs so much? Why, the whole world of knowledge is not worth that child's prayer to dear, kind God'! I say nothing of the sufferings of grown-up people, they have eaten the apple, damn them, and the devil take them all! But these little ones! I am making you suffer, Alyosha, you are not yourself. I'll leave off if you like ”