Continuity mistake: As Cinderella descends the staircase after her wedding to The Prince, she is obviously wearing a long sleeved gown. When she waves through the window of the carriage, however, the gown is short sleeved.
Other mistake: When the clock strikes 8 o clock, the 11 (XI) on the clock reads 12 (XII) in roman numerals. This is just in-between the scene with the mice making Cinderella's ball dress and the scene where the carriage arrives at the home to pick the stepmother and stepsisters up for the ball. (00:36:50)
Continuity mistake: The Fairy Godmother turns the four mice into horses. When they change back three of the mice are the same, but one is different. It goes from Jaq, Gus and the twin mice to Jaq, Gus, one of the twins, and the little mouse.
Continuity mistake: After throwing the bookends away, the King leans on the table and stares at the Duke. In the first shot the King's tummy lies on the table and his left hand grabs the left edge. A shot later he is half a meter away, standing by the table with both hands lying by his belly.
Continuity mistake: When the king throws his crown and breaks the window, note the lower part, a part shaped like a V is standing out. In the shot following it's now shaped like a lower case R.
Answer: A cause of death was never revealed in the movie versions. In the Grimm fairy tale, the father left on a long business trip, but took ill and died during the journey.