A child will ask if they want two waters because they need a grown-up's consent. Children aren't allowed to have whatever they want, they need to make sure it's okay and get consent first.
"Of course my child, you have my consent," comes the voice of the Shougun (しょう). The Shougun is very pleased by this child, because he expects everyone to ask for consent around him.
Currently there are no similar looking kanji which exist in the WaniKani learning system