Open Question: Check Cashing problem!?

I got a check from the house where i live. I've been paying taxes for the past 2 years for the house.. It was under my name and my Uncle's name. Unfortunately he died 1 month ago... =( The thing is that i got a check from the Cook County treasurer office Under his name. Its a tax error for 2008 and 2007, over 7,000 dollars how can i cash this check?? What should i do?