People who had to earn a living by manual labour, or even skilled labour, but still had no money to send their children to school, would have been teaching their sons the trade from the earliest possible age, a) to ensure they passed on the skill, and b) just for an extra pair of hands to help earn their keep. If anyone had a right to complain that they didn't have enough time to bond with their son, it should be his mother!
Well, there were regional differences. In England, from at least the late middle ages it was the custom at all levels of the social hierarchy for parents to send their children (both boys & girls) out from a young age to be educated/trained by others: in the aristocracy they became pages & maids-in-waiting, in the trades they became apprentices, and in the farming classes they became farm servants. This practice was remarked on by visitors form the Continent as a sure sign that the English didn't love their children. But the English regarded it as the opposite, the theory being that they would treat their own children too softly and let them grow up lazy & ignorant, while they wouldn't be as indulgent with someone else's, and the practice persisted as an English peculiarity for many centuries. (Though eventually young gentlemen were sent away not to other households but to schools.)