Property lien from 1979 taxes

[Krista Moreno]

I appreciate this platform and all the great information and help! 

My problem is on a home I was going to inherit from my aunt in Florida. A couple years ago the IRS asked for her 1979 taxes and she didn’t have them to prove them. So she claims they’ve put a lien on her house. How would I go about finding this lien. And is this legal for the IRS to do with them being so many years ago? I don’t have the money to hire an attorney. And I’m afraid when she passes if the house is to go to me I’ll have to pay the lien amount in order to put it in my name. 
Any insight or help on what I should do?