LeBron James isn't just Bronny's dad and teammate, he also acted as his coach on Thursday ... giving the Lakers rookie some sound advice during their game against the Suns.
The moment happened during the preseason matchup at the Footprint Center in Phoenix ... where Bronny played 17 minutes in the overtime win.
At one point in the contest, LeBron -- who didn't suit up for the tilt -- was talking up the 20-year-old guard near the bench .