Your deceased mother is entitled to the stimulus check and here is the information from the Form 1040 Instructions, page 57 (printed below for your convenience).
Generally, you are eligible to claim the recovery rebate credit if in 2020 you were a U.S. citizen or U.S. resident alien, weren't a dependent of another taxpayer, and have a valid social security number. This includes someone who died in 2020, if you are preparing a return for that person. Use the Recovery Rebate Credit Worksheet to figure the credit, if any, you can claim. For more information on the recovery rebate credit click the hyperlink.
You can be confident to enter the correct information in TurboTax Online exactly the way you are doing it.
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