This was Judith Barsi's final film. She and her mother were murdered by Barsi's father a year and a half before the film's release. The ending theme, "Love Survives," is dedicated to Barsi's memory.
MGM shortened a scene involving Charlie in Hell to avoid a possible PG rating. Don Bluth owns a private version of the uncut film that has never been released on home media.
Burt Reynolds and Dom DeLuise, who had developed a rapport after starring in several movies together, insisted that Don Bluth leave the room during recording sessions so that they could improvise off one another better. Bluth agreed and allowed Reynolds and DeLuise to ad-lib extensively. Bluth later commented "their ad-libs were often better than the original script". Reynolds was more complimentary of the draft, saying "Great script, kid", as he left the studio.
Don Bluth was so heartbroken over the death of Judith Barsi that he based Anne-Marie's design and mannerisms on her, to honor her memory and cope with the loss. Burt Reynolds was also so heartbroken that he asked if he could redo his "Goodbye isn't forever" lines, and did so while looking at a photo of her. Reportedly, it took Reynolds nearly 70 takes to get the lines right, and in the final film his voice can be heard breaking, especially on the line, "I'll miss you too."
When the heavenly whippet looks in Charlie's records, his mother and father are named "Loni A." and "Burt R.", and look like canine versions of Loni Anderson and Burt Reynolds (who were together at the time.)
T. Daniel Hofstedt: The Additional Storyboard Artist and Character Animator of the movie sings as part of the 'You Can't Keep A Good Dog Down' Chorus and appears as the voice of the Crowd Walla at Racetrack & Casino.