I'm trying to file my mothers taxes, can I file them through my account?

[VolvoGirl]

No.  

Online is only good for one return per account. But you can use the same email address for 5 accounts. Online is only good for 1 return per account. So don't use your account or you will overwrite your return.

Start another Online return here. Sign up and start a new account.
https://turbotax.intuit.com/personal-taxes/online

The Desktop program can do unlimited returns and efile 5 federal for free. You can buy the Desktop CD or the Download program here,
https://turbotax.intuit.com/personal-taxes/cd-download