First, it seemed to me the Jedi child thing was based on a throw away line from Yoda in Empire. I took it from that as Yoda baiting Luke to try harder. The PT says I was wrong. So whatever.
Now even if it was intended from the begining by the great and powerful Lucas, then I see this whole Jedi taking children under their care as a sub conscience mirror to his own life as a father by adopting his kids.
George has made a saga that in affect says to kids --to his kids, --that the greatest, most trusted guardians of the galaxy are the ones who don't have natural parents raising them. And the only way to be great Jedi is if you're adopted by the Jedi, --or the Lucas,--then you too can change the ways of the simple minded.
And let's not forget that one of the kids had a cameo as a Jedi youngling.