You will need the userID and password she used AND access to her phone for the verification code that will be sent ... so that is not really an option.
You can get copies of the returns or transcripts from the IRS :
You can get a return transcript from the IRS for free : http://www.irs.gov/Individuals/Get-Transcript
For a $50 fee you can get a copy of the return from the IRS: https://ttlc.intuit.com/questions/1901218-can-i-get-a-copy-of-my-tax-return-from-the-irs
