What does the title of Chapter 4, "In the Shadow of the Young Girls in Flower" allude to?

This chapter title alludes to a volume of Marcel Proust's In Search of Lost Time. The volume examines themes of memory, spacial identity, the nature of art, and homosexuality, all of which relate to Fun Home. The author makes several comparisons between her father and Proust in the chapter, particularly in terms of homosexuality.