Mom/Sis stayed with me the entire year of 2017. Mom was unemployed & I took care of my sis most of the year, letting me claim my sis on return. What docs do I need?

[Critter · Accepted solution]

You don't need any docs upfront ... if the IRS was to question it later you may need to prove they lived with you and that you supported them.   If your mom had less than $4050  in income then she may also be a dependent... follow the interview to determine if she qualifies.