During filming, Asia Vieira (Molly) became very fond of Leonard Nimoy. While filming she had seen the ending of Star Trek II: The Wrath of Khan (1982), and became very upset when she saw Spock had died. Being only six at the time, she thought it was Nimoy who had died in the film. The next day on the set, she was very happy to find out that he was okay, and it was just part of the film. She ran over to him and gave him a big hug, and told him she was glad to see that he was better.
During the filming of an emotional court room scene with Diane Keaton concerning the custody of her daughter, it was discovered that the two cameras used to film the scene simultaneously had different types of film, which could not be edited together due to their vastly different looks (one was for a soft look, the other normal film). Director Leonard Nimoy felt bad about having to have Diane Keaton film it again, because she had done it so well. He showed up at her dressing room door with two dozen roses in his arms. He gave the roses to her first, then gave her the bad news about having to re-shoot the scene. Diane Keaton took it well, and had no problem with having to re-shoot the scene.
This was the only pure drama directed by Leonard Nimoy. Star Trek III: The Search for Spock (1984) and Star Trek IV: The Voyage Home (1986) were science fiction films while Three Men and a Baby (1987), Funny About Love (1990) and Holy Matrimony (1994) were comedies.
Although Teresa Wright plays Diane Keaton's grandmother, she was only 27 years her senior in real life.