Marriage Story (2019)

In the scene where the father and son walk into the office and the boy runs over and feeds the fish in the aquarium, the saltwater fish worked in a 50-gallon glass tank. The fish trainer checked the water temp throughout the day.

In the scene where the actors walk into a room and see a boy petting a cat on the floor, prior to shooting the scene, the trainer placed the cat next to the young actor on the ground. The boy pet the cat. They reset and did it again.