Board Thread:Theories and Speculation/@comment-27717552-20160513151229/@comment-26773508-20160609071857

Yeah the Parent-Child description doesn't really capture it accurately. One could say that was the case if we're talking about the initial depiction of Chidori/Raikiri in the anime i.e. Kakashi/Sasuke releasing lightning chakra from a central spherical lightning core from their palms. But Kishi later changed the Chidori/Raikiri to look like what it is today, i.e. bright electric chakra wrapped around the entirety of the user's hand. So while the Rasengan definitely inspired the Chidori, its present form is actually more close to the Raikage's Four-Finger Hell Stab than it is to the Rasengan.