@AlphaBenson
In Wind Waker it is clearly stated that WW Link is not related to the Hero of Time at all and therefore cannot be related to Skyward Sword's Link. HOWEVER, remember what Demise said? That as long as there is someone who INHERITS the SPIRIT of the Hero and the bloodline of the Goddess, his hatred will always spawn. The goddesses are the ones that reincarnated the Hero of Time within WW Link. Also in relation to an earlier post by you, remember what Shiek said? That the Master Sword is a key or ship that lets the bearer travel up and down Time's river, so that is why the Master Sword returned with Link. That sacred sword cannot have duplicates because it was the main reason why Link was able to do what he did in OoT.
However I am a little confused as to why WW Link was able to pull the Master Sword from its pedestal when he wasn't of age yet...I think it might have to do with the fact that the Master Sword had lost its power and it had just become a "normal sword". When Link powered up the sword again at that point he was recognized as the Hero of Winds and therefore did not have to go into a deep sleep to come of age to use the sword.