Agreed that genetics can be very complex and a lot can skip a generation and a lot from the grandparents can be seen in the grandkids. Agreed. I am actually trying to play the Devil's advocate as a way to defend that Joey theory which I never heard of until today. It doesn't really matter unless if they reveal it in the third season of Fuller House this year maybe, 2017. Beyond that, as far as we know, Danny was the father of those 3 characters, those 3 girls. The video theory came from Cracked and it is mostly just a joke. But it is possible & it would be kind of like Game Of Thrones and kind of crazy like Star Wars Vader is the father of Luke Skywalker whom kissed his sister, Leia, crazy. I kind of like entertaining crazy theories sometimes.