I’ve found a Shrinking Scene from a 1979 Russian Animation Short: Masha And The Magic Jam.
The film tells us how it is bad to say lies and that secret always becomes obvious. For children. Masha eats grandmother’s jam and says that it was made by the cat. The grandmother tells her grand daughter that jam is magic: who eats it he will decrease. It seemed to Masha that she became small and the cat wishes to punish her for the deceit. Then the girl recognizes her fault.
The Shrinking Scene start at 5:03
https://youtu.be/-M4riI2mlLs