After the shinki reveal it's put into question if the other two are his real kids I think yodo is gaaras only legitimate child. For one she has gaaras eyes and temaris hair. Also with the gaara novel it's hinted that gaara found someone to marry so it's possible he atleast has one biological child.
Also a lot of people noticed shinki looks a lot like kankuro and uses his puppet ability. This made me have a theory that only a heir that can use iron sand can become the next kage for some reason gaaras wife died prematurely forcing gaara to adopt shinki from kankuro.
I think Araya is the only child that isn't apart of kazekage lineage.
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Also a lot of people noticed shinki looks a lot like kankuro and uses his puppet ability. This made me have a theory that only a heir that can use iron sand can become the next kage for some reason gaaras wife died prematurely forcing gaara to adopt shinki from kankuro.
I think Araya is the only child that isn't apart of kazekage lineage.