Board Thread:Theories and Speculation/@comment-26720308-20150717151638/@comment-3568954-20150721182652

Either way no matter what the Hagoromo clan would be Decended from Hagoromo more than likely the clan is not descended from indra as they didn't have Sharingan they may have descended from a third child(and yes they say he had 2 sons but they don't say he didn't have other sons) or daughters.

we don't know

and the uzumaki clan isn't close related to senju clan its an offshoot of the senju clan just like the hyuga branch family is a branch off of the hyuga the uzumaki clan originated in the senju clan