You can never include your daughter's income from working in your tax return, whether or not you claim her as a dependent. If she reports the income it has to go on her own tax return, not yours.
If the $9,000 is on a W-2, and that is her only income for the year, she does not have to file a tax return.
If the $9,000 is self-employment income, such as cash, non-payroll checks, or digital payments, or it's on a Form 1099-NEC, she is required to file a tax return. She will have to pay self-employment tax even if she doesn't have to pay any income tax.
VERY IMPORTANT: If she files her own tax return, make sure she checks the box that says someone can claim her as a dependent.
This answer is specific to the facts stated in the question, and may not apply to someone else whose details are not exactly the same.
