The claims having been filed, it is then the duty of the court to hear the claim upon a regular trial. The same proceeds are had to determine the justness of the claim upon the trial of the cause, and a claimant is entitled to prove his claim against the estate by his own oath, unless objection is made, in which case the claim must be substantiated by competent testimony. A judgment regularly obtained, or a certified copy thereof, is taken as duly proved, likewise all instruments in writing signed by the decedent if the handwriting is established and proved; all other demands must be properly and sufficiently proved. (b) It is proper for the estate having a counter claim against the claimant to have the same adjudicated upon the hearing of the original claim; and if the court is of the opinion from the evidence that the estate is not indebted to the claimant, but that the claimant is indebted to the estate, judgment may be rendered in favor of the executor or administrator.

6 Rassiur vs. Jenkins, 170 Ill., 503.