You are correct that you will need to complete the amended tax form (Form 1040X) to change the status of your daughter's return. The 1040X form is not available yet in TurboTax, but is scheduled to be by 3/8/19. Once the form is available, the link below will be updated with instructions for how to prepare and file the 1040X form. Note that amended tax returns must be printed and mailed as they cannot be e-filed.
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