What detail in the description of the Ewell cabin indicates that perhaps Mayella is different from the rest of her family in To Kill a Mockingbird?
Scout remembers that she saw a "row of red geraniums in the Ewell yard." These flowers, planted by Mayella, are the one bright spot in an otherwise ugly and chaotic environment, and they indicate that Mayella, alone among her other family members, retains an appreciation for beauty, and struggles to maintain it in a life otherwise devoid of anything refined.
Mayella has grown up in violence and squalor. Her father is a coarse, violent drunk who is completely lacking in principles and decency. His wife is deceased, and it has fallen to Mayella, as the oldest, to take care of the house and raise the younger children as best she can. With her depraved father in charge, Mayella has been subjected to every atrocity imaginable; her life has been one long sequence of horror and abuse. Yet despite her upbringing and the conditions in which she is forced to live, Mayella has a spark of goodness in her, a part of her which recognizes and yearns for something better. Scout catches a glimpse of this part of Mayella when she sees something "somehow fragile-looking" in the otherwise "thick-bodied girl accustomed to strenuous labor." She is able to explain this special quality in Mayella by comparing her to her father - Mr. Ewell is filthy, customarily covered with "protective layers of dirt," while Mayella looks "as if she trie[s] to keep clean." It is this contrast that puts Scout in mind of the geraniums; there is something of refinement about Mayella which is lacking in the rest of her family, something of goodness, which has not yet been snuffed out (Chapter 17).