Why were the parents unable to support their children's basic sustenance in the beginning of the Industrial Revolution? Children worked "the farm" from time immemorial, so the concept of children working was not alien, but the work required of them in the industrial revolution was exetremely harsh compared to the work expected on a farm.
As work migrated to the cities and the work-to-food-to-mouth was less direct, the worthless class (wives of the rich, etc) had nothing better to do than to butt their noses into everyone else's business. Thus "child labor" came under scrutinization. While condititions werre deplorable, that had nothing to do with the root issues and nothing to do with the age of the workers. As child workers were restricted, this hurt the working families, and led to a desire for government assistance, as families who were originally dependent on support from the work of the entire family, were now dependent on one income to support all the hungry mouths. Thus through government regulation, the need for taxation(theft) swelled to support actually uneconomic movements in the market. Thus, the government subsisdized the Industrial Revolution. In foreign markets, where people complain about "child labor", the same situation presents itself. As the government and the UN remove the ability for people to live in a sustainable way off the land, children supporting their own mouths is the only way for borderline impovrished families to live. The ne'er-do-wells focusing on the symptom and not the cause, are actually making life worse for such families, instead of "helping the children".