Section 11-103 - Suits against joint debtorsIn a contract action brought against alleged joint debtors:
(1) The plaintiff need not prove their joint liability as alleged in order to maintain the action;(2) The plaintiff may recover as in actions in tort against one or more of the defendants who are shown by the evidence to be indebted to the plaintiff; and(3) Judgment shall be entered in the plaintiff's favor against one or more of the defendants as fully as if the defendant or defendants against whom the plaintiff fails to establish a claim had not been joined in the suit.