A talking mule?
Chill Wills (July 18, 1902 – December 15, 1978).
Theodore Childress "Chill" Wills was an American actor and a singer in the Avalon Boys Quartet. One of his more memorable roles was that of the distinctive voice of "Francis the Talking Mule" in a series of popular films. Wills' deep, rough voice, with its Western twang, was matched to the personality of the cynical, sardonic mule. As was customary at the time, Wills was given no billing for his vocal work, though he was featured prominently on-screen as blustery General Ben Kaye in the fourth entry, Francis Joins the WACS.
Wills appears with Donna Reed in the movie, See Here, Private Hargrove (1944).