You don't enter her income on your return. It would only go on her return if she is required to file one. If the W2 is the only income she has and it is less than 6,300 she doesn't have to file except to get back any withholding taken out.
If it is more than 6,300 she has to file. Be sure on her return she checks the box that says she can be claimed on someone else's return. That is very important.
Online is only good for 1 return. But you can use the same email address for 5 accounts. How to start another return in the Online version
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