'Son' in the Bible

Words of a preacher, son of David, king in Jerusalem:

There is one, and there is not a second; even son or brother he hath not, and there is no end to all his labour! His eye also is not satisfied with riches, and he saith not, 'For whom am I labouring and bereaving my soul of good?' This also is vanity, it is a sad travail.

And that wealth hath been lost in an evil business, and he hath begotten a son and there is nothing in his hand!

Happy art thou, O land, When thy king is a son of freemen, And thy princes do eat in due season, For might, and not for drunkenness.

And further, from these, my son, be warned; the making of many books hath no end, and much study is a weariness of the flesh.