Answer:
When she looks at Rachel and Lucy, Esperanza immediately notices that the two girls are sisters, especially because of their identical thick Popsicle lips. However,when she thinks deeper, she sees even more similarities between herself and Nenny. For example, they have the exact same laugh. When the four girls are playing outside on Mango Street, Esperanza spots a house that she thinks looks like Mexico. Nenny bursts into the same laugh, agreeing that the house, indeed, does look like Mexico. Lucy and Rachel become closer to Esperanza, not only because of the friendship they provide, but also because of the friendship they strengthen between Esperanza and her own sister. Through similarities between Lucy and Rachel, Esperanza begins to notice all the similarities she shares with her young sister. She hears Nenny laugh and knows that it is identical to her. I hope that helps.