Esperanza, the main character, is a really good girl who is recording her understanding of the world in short stories about her world in the barrio. She is seeking to better understand herself and her place in the world and she relates to older women who dress a certain way. She is inquisitive and thoughtful and reflective in the way she looks out at the world.
Alicia is burdened and fearful and broken down because of her poverty.
Nenny is much like Esperanza and they relate to the world in similar ways. She is full of energy and life.
Mama is authoritarian to the girls and very demanding but she is also reflective and hopes very much for a better life for the girls than the one she has had.
Papa is something of a hopeless romantic, filled with hope that they will win the lottery and somehow escape grinding poverty.