'Child' in the Bible

Thus saith the LORD; For three transgressions of the children of Ammon, and for four, I will not turn away the punishment thereof; because they have ripped up the women with child of Gilead, that they might enlarge their border:

And I will turn your feasts into mourning and all of your songs into lament, and I will put sackcloth on all loins and baldness on every head. And I will make it like the mourning for an only child, and its end like a bitter day.