She admits that she gave birth to Dewey Dell "to negative Jewel" and to Vardaman to "replace the child I robbed him of." Thus Dewey Dell, born only as a replacement for, or to negate, Jewel, is the child who most resembles Anse.
Thus she decides to close herself to Anse, who represents only the ineffectuality of words.
Only through violence, and not through words, can Addie feel that she is living.
In Jewel's life, this violence is displayed through the love and violent treatment of his horse, and the salvation is seen through his rescuing Addie's body from the river and the burning barn.
Thus Jewel, who was born as a result of Addie's desire for violence, responds to all events with violent and impetuous actions, and he seldom says a word except some violent oath or curse.