My question involves an auto loan or repossession in the State of: IL

My dad signed on a loan (2004). Loan was defaulted on, and car was repossessed and sold at auction. Person who held the loan declared Chapter 7 bankruptcy (2006). Dad just received notice that he's in arrears for car loan (11k+). Can the creditor do this? My dad is 77, works part-time at Home Depot to supplement his SS check and doesn't have a pot to *** in...any chance we can get out of this?

Really appreciate the help...feeling a little desperate...