That was going to be my reply. “Young” is relative. Then they had been working on farms, in the family trade since very young. They were not “young” as we think of it today.
Don’t care how you slice it...18 is young. Just because they were running businesses and farms does not change their age. Women/girls were getting married and having children anywhere from 14-18. They were still young, but acted like adults not permanent infants. We do not allow our youth to grow up soon enough.