The author does this to reinforce the protagonist's Latino ancestry and to reinforce the idea that many of the family problems are caused by cultural differences.
"The Horned Toad," tells the story of a boy who needs to live between his father and maternal grandmother and the cultural conflicts that exist between them. In this story we can see that:
Therefore, we can affirm that the best way for the author to expose his grandmother's Latin origin, without using disrespectful stereotypes, would be to add expressions in Spanish to her speech.
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