“Kid brother” in Japanese
Short answer
Kid brother in Japanese is “弟” (tei). Full meaning: younger brother, little brother, kid brother; brother-in-law (spouse's younger brother or younger sister's husband).
Other ways to say “Kid brother” in Japanese
弟妹
otouto younger brother, little brother, kid brother; brother-in-law (spouse's younger brother or younger sister's husband)
おとうと
otouto younger brother, little brother, kid brother; brother-in-law (spouse's younger brother or younger sister's husband)
をとうと
otouto younger brother, little brother, kid brother; brother-in-law (spouse's younger brother or younger sister's husband)
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