Hard to tell. They're both the same size & sneak around in the off season. I think LBJ has a better table manners though.
A couple of things just for the record. a) Chris Paul sent his kids to John Cooper this past year, a SPC school in the Woodlands b) They are moving into town and he is looking to send them to one of the other private schools in the area (St. Johns, Kinkaid, etc.) c) I doubt LBJ would send his kids to either of those schools as they aren't considered good basketball schools. Justise Winslow went to St. Johns but it was truly an aberration... if LeBron were to choose Houston I would expect Bronny to go to St. Thomas, Strake, or one of the "big" private schools.
This is not even unreliable hearsay. Unreliable hearsay would be your friend heard from his friend ....