When you say "they," are you talking about the illiterate person and his spouse? Or are you misusing/confusingly using a plural pronoun to refer only to the illiterate person?
Subject to how you answer the question, it is likely that both the illiterate person and his spouse are liable for 100% of the contract price. If the illiterate person signed the contract without asking that it be read to him, then he apparently didn't care what the document said. That being the case, what would make you think that he might not have liability? Did the other party to the contract know or have reason to know that this person was illiterate? Same question about the cancer meds.
Briefly describe the circumstances that led to the signing of this contract. What is the status of the remodeling work? How much has been paid and how much remains unpaid? Please be mindful that, when telling a story, indiscriminate use of plural pronouns may render what you write ambiguous.
Huh? In your original post, you wrote that this person "sign[ed] a contract for remodeling a house along with [his] spouse, but now you're telling us that he doesn't have a spouse? Was this contract signed when he was married? How long ago was this? Was the contract to remodel the house in which the three of you live? If so, who owns the house? Why would some mortgage company be seeking payment for a home remodeling contract? What does "trying to go after" mean?
