Mrs Hardy is annoyed that her husband Oliver seems to spend more time with his friend Stanley than with her. After a furious argument, Mrs Hardy says that she is through if Ollie goes out with Stan again. Stan suggests that Ollie adopts a baby, which he does. Unfortunately, his wife has left their apartment on returning, and a process server delivers a paper informing Ollie that she is suing him for divorce, naming Stan as correspondent. The boys are now left to look after the infant on their own.
You can now watch Their First Mistake online on the following streaming providers in the United States.
| Directing | George Marshall | Director |
| Writing | Stan Laurel | Writer |
| Production | Hal Roach | Producer |
| Editing | Richard C. Currier | Editor |
| Camera | Art Lloyd | Director of Photography |
| Production | Lawrence Tarver | Casting |
| Sound | James Greene | Sound Recordist |
| Sound | Marvin Hatley | Music |
| Sound | Leroy Shield | Music |
| Writing | Oliver Hardy | Writer |
| Writing | James Parrott | Writer |
| Writing | Charley Rogers | Writer |
