In the same series of animations, there are Twelve Months, The Story of the Groundhog, Swan Lake and so on.
It seems to be a collection of world fairy tales, the name of which is unclear, but it is definitely not a collection of fairy tales of windmill waves (the animation is very rough)
It's about a group of children of several years old and they have a very good relationship.
But a child died, so that others could not see him all day.
I don't remember the story of him silently guarding his friends. I hope you can find it as soon as possible.