Inherited land with house and the home owner died.

[Al Mcbee]

My grandmother has owned a plot of 70 acres for many years free and clear. She leases out some of it for pastures and other farming activities. Also, she let her brother (and his wife at the time) put a pre-manufactured home to live in on a portion of the land as well. 

My grandmother gifted me the 70 acres about a year ago. Just recently her brother had passed, and I just found out that there is still a $30k note due on the home. My grandmother did not have her name on any of his stuff, nor did she ever charge him rent to live on the property.

My question is, who is responsible for the balance of the note? 

Thank you in advance, because I would like a little insight as which direction I need to go.