<p>Shinki has vague traits shared by Kankurou. This could mean he is Kankurou's son, but it could also mean he is Gaara's as both brothers share genetics of Rasa. Furthermore, the Kazekage Clan is not the only clan to have magnet release. Physical and ability-based traits don't really say much at this point scientifically. Appearance wise he could be the kid of Ameno and Mikoshi (though that says little about where he'd get the KG, but still, my point still stands that what we know doesn't confirm anything)
</p><p>And shared interest and style isn't a genetic factor, so using face paint and puppets as an argument doesn't make much sense, those are both common to Suna in general.
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