Cuckoo on a Choo Choo

Larry and Shemp are living in a stolen railroad car. Larry wants to marry his girlfriend, but she won't consent until Shemp marries her sister. Shemp however, is constantly drunk and in love with "Carry", an imaginary giant canary. Moe is an investigator from the railroad, sent to discover how the car was stolen from a moving train. Moe is also in love with Shemp's girl. Shemp winds up with both women, but still prefers his imaginary canary (imdb)