How does the author use foreshadowing in Desiree's Baby?

Chopin uses subtle foreshadowing in preparation for the revelation of Armand's ancestry. Désirée is described as having fair skin and gray eyes, wearing "soft white muslins and laces." As she walks away from her home for the last time, dressed in a white garment, the sun brings out a "golden gleam" from her brown hair. Armand, however, is described as "dark", and his racial ancestry is further foreshadowed in Chopin's repetition of the color yellow. The plantation house is yellow, as is the baby's nurse. None of Armand's slaves are described as black, and one slave is even called La Blanche (the white woman), while the young slave who fans the baby is a quadroon (a person of one-quarter African ancestry). In fact, it is the appearance of the quadroon boy who sparks Désirée's comprehension of the racial ancestry of her own child.