After you file

First, make sure your daughter is an eligible dependent and listed on your return. Now to amend.

1. Log into Turbo Tax assuming you use Turbo Tax online
2. When you reach the landing page, scroll to the bottom where your tax returns and documents are.
3. Select 2020, and click on the option to amend and change return.
4. Answer the questions about why you are amending
5. Once you begin working in your return, your refund monitor will reset to 0. 
6. Once you are working in your return, go to federal review.
7. First question will ask if you and your spouse received stimulus payments, here you will say yes.
8. Then it asks you to double check the amounts you received.  Assuming you received full stimulus payments for yourselves and your child, it should read $2900 for the first round and $1800 for the second round you didn't receive this, you will indicate no and an additional dropdown will generate asking how much money you did receive in the first and second payment.
9. If it reads $2400 for the first round and $1200 for the second round, then it doesn't recognize your child as a dependent and you will need to edit the information in the MY INFO section of your return to make sure she is a eligible dependent.
10. Examples, I gave assumes you have one child and not taking into account you may have other children that were also eligible for the stimulus payments.