No....Maybe?No....

loooool who knows aside from kishi
glad to know im not the only one who thought of this, thought i was a lone wolf on this one lolyou are not silly and i have thought of this possibility. however i wouldnt go so far and say descendants. they dont need to be related in order to get a power up. kakashi did talk about teamwork before so they have a part to play in this fight. Also, the fact that kakashi and sakura are too weak to help leads more strength of their need of a power up.
P.s. I have had another thought with the sages brother and neji's reappearance, but this still requires time to develop