Stephen,
They did have household help and they called them domestics. One of them was a black girl of about 17 but that was not uncommon for that time. The Lincolns were what we would call upper middle class today and I don't know about where you live but up here there are still families who hire domestics to help with the cleaning and cooking and laundry, etc.
They also had a couple Irish immigrant girls who worked for them. Kind of like apprentice training for marriage.
FC