I need to file 2016 taxes for my Dad who passed in 2016, do I have to create an account for him or can I log in on my Turbo Tax account and file for my Dad?

You will need to create a new user id when starting a new return as using the same account will overwrite the return already filed or started. Please see the following TurboTax FAQ on how to start another return in TurboTax Online:

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