"A Menina do Mar" was first story of Sophia for children and was published for the first time in 1958. Having the beach as scenery, this tale reveals a story of friendship between a boy and girl in the sea. Each lives in their world, the boy in the land and girl in the sea, but the curiosity of both leads them to want to share these differences: the girl gets to know what is love, longing and joy; the boy accepts to live with her under the sea.