not bad theories,,,,, ,,,
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(<(((o)))>) < who's that sexy thing over there?!) not bad! not bad! .... ...
the sage was never, an uzumaki. when you put the sage has an uzumaki, the line gets messed very very bad, why madara need to get hashirama cells if he uzumaki?? or aleast has some in him?? and many others,
my theory is that, the Sage did not have rinnegan by birth, he was not an uzumaki, then you might ask how the heck did he beat juubi?! his treasured tools.. thats right... i believe the Sage used his infamous tools to defeat the beast and sealed it within himself
and by being the juubi's host, he got rinnegan and thats how it came to be,
how do uzumakis come the picture??
i believe uzumakis are one of the sons of the YOUNGER son of rikudo sennin, just like rikudo, the younger son in his old age gave to the uzumaki son the ''life force'' he received from the sage, and the rest he passed on to his other son, which carried on the senju path.,
this could also explain the uzumakis and senjus being distant relatives! their ancestors could have just been brothers, making uzumaki and senjus. ''cousins.