Osminozhki (1976)

In the underwater world lives dad-octopus. His wife and several beautiful little octopuses live together with him. Dad takes his children home, but the house key is missing. Kids are not confused and hit the house through an open window. The octopus also tried to crawl there, but then the door opened, and the octopus mother came out. Parents faced a difficult task - to wash their children.