"The fact that the witness who gave the uncontradicted testimony is directly interested in the outcome of the litigation is a circumstance important in weighing the testimony given." (See, also, Barham v. Khoury, 78 Cal.App.2d 204 [ 177 P.2d 579], and Broderick v. Koehler, 92 Cal.App.2d 813 [ 207 P.2d 1070].) [2] In the present case appellants' witnesses were interested in the outcome.