Not sure I picked the correct category for this question.
My daughter (36) who is disabled receives disability and food stamps. She has a daughter who graduated high school in May, started a job on 7/19 and is turning 18 in August will my daughters benefits change? Does she have to update her application? They both live with me and my husband and we provide over 50% of there living expenses.

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My daughter (36) who is disabled receives disability and food stamps. She has a daughter who graduated high school in May, started a job on 7/19 and is turning 18 in August will my daughters benefits change? Does she have to update her application? They both live with me and my husband and we provide over 50% of there living expenses.

You have not indicated which state you are in. The answer to your questions would depend upon that. I expect that your daughter should update her application (to state that the grand-daughter is now working); and that she could find out for sure by asking the agency to which she initially applied.