Yes, you can file a tax return for your mother as her Power of Attorney (POA).
When filing her return in TurboTax, prepare the return as usual with her information. When prompted about who prepared the return, indicate that you prepared it as her authorized representative. In the signature section, sign your name followed by "POA". Keep a copy of the POA with your records.
It's also a good idea to get a signed Form 2848 so that the IRS can discuss her return with you.
