How old is Phoebe when she brings lunch out to the field? As she comes out to the field, how is she described by the narrator? What are her responsibilities?

Phoebe is seven years old. She is lugging a heavy basket up to the workers in the field, sweat on her brow, but looks happy. She behaves as an older girl would, but still has the dimpled hands of a child. Phoebe's responsibilities include working in the house with the cooking and cleaning, and bringing lunch out to the farm hands.