Sirach 30:8-10

Revised Standard Version Catholic Edition

⁸ A horse that is untamed turns out to be stubborn,
    and a son unrestrained turns out to be wilful.
⁹ Pamper a child, and he will frighten you;
    play with him, and he will give you grief.
¹⁰ Do not laugh with him, lest you have sorrow with him,
    and in the end you will gnash your teeth.