Sometimes, it is difficult to communicate a child's emotions, but through the magic of drawings, it is possible.
The Yuzuki Family's Four Sons (Yuzuki-san Chi no Yon Kyōdai) is a sweet and wholesome story about four brothers who are left without their parents. Fortunately, the oldest brother is old enough to get a job, which makes possible for kids to stay together. Their love for each other is apparent, even in Minato, who is the least interested in telling his brothers how much he loves them.
Beware the spoilers; we will discuss an animation technique used to show Mikoto's feelings.
Naturally, and it is very realistic, the brothers do not always get along well. The second episode tackles some very dark emotions, up to and including not wanting someone's younger brother to exist. And while such thoughts are terrible, sometimes siblings do feel like they have to compete for parents' affection and, as a result, wish for some truly terrible things.
Episode two is special in its use of visuals, which are fit for exploring those dark, half-understood feelings. The episode is about Mikoto and Minato dealing with being so close in age, Mikoto being jealous of Minato getting all the attention and Minato feeling insecure next to a very well-behaved and academically successful brother (even though it is just pre-school, Mikoto is shown to be better at most things he does).
With this episode's two main characters being so young and with Mikoto being unable to name most of the feelings he experiences, childhood drawings are used to show his emotions. Sometimes it is a full picture, but often it is just an angry squiggle on a dark background, which shows how difficult it is for a tiny human to process something as complex as envy toward someone you love.
Sibling Rivalry Gets Real
When Mikoto tells Minato that he wishes his brother was never born, it is very clearly done in a fit of rage, and the anime's visuals show how the angry squiggle finds itself transferred into real life by making Minato's screaming a continuation and a part of that drawing.
Mikoto is the quiet child, and he does not cause trouble, but the anime's visuals show that he has been harboring resentment for a while, and eventually, it spills into the real world. The visual of drawings, as a result, is very good at showing how difficult it is for a child to deal with all that emotion trapped inside.
The ending of the second episode shows Mikoto making peace with his position as an older brother, and he apologizes for the horrible words he said while Minato also apologizes for his own words and actions. Since then, the drawings are much calmer and express positive emotion with flowers and smiles incorporated into them.
This decision to use childhood drawings for Mikoto's emotion is both creative and very effective in delivering the children's experiences.