Like all Rommely women, Katie came "made out of thin invisible steel." The daughter of Austrian immigrants, Katie is hardworking and proud. A life filled with poverty and children has made her hard and detached, and has catalyzed her survivor instinct. While Johnny succumbs to hardship, Katie perseveres, and this is a defining characterization for each of them. Hard times only make her fight harder, and in the end, her children's success makes her struggle worthwhile. Although she changes little throughout the novel, she is softer before the birth of her children. She is romantic enough to fall in love with Johnny, and marry him, all because he could sing and dance. By the time Neeley is born, Katie loses all softness, knowing that she can depend on only herself to provide for her family.
Katie is symbolic of lower-class women in urban America at the turn of the century. She is a second generation American, and reflects the values of an immigrant background. She functions in the novel as a symbol of what the American dream can be. When Mary Rommely gives Katie advice at the beginning of the novel about how she should raise her children, the reader realizes that Katie is the means by which her children will live better lives than their parents.
Although Katie is a valiant character, the novel does not value one parent over the other: both have strengths and weaknesses. Katie never sees any of Francie's writing, for instance; she does not figure out a way for Francie to go to an enchanting school; she brushes her fears aside. Still, Katie provides the means by which Francie and Neeley survive.
Although Katie prefers Neeley to Francie, she loves both her children fiercely. She will make any sacrifice so that they may have an education. Every time a penny goes into the tin-can bank, it is because Katie gives up a little heat, or a little food. Katie worries sometimes that her children are too protected—that they see romance in a mean life, and that without life's cruel truths they will not fight to get out of their poverty. Education, she believes, will cure her children of poverty and meanness. Katie refuses charity in all its forms, teaching her children to grow up with dignity.