Courtside For Bronny's McDonald's Game ...

LeBron James took a day away from the Lakers to put on his Dad hat and watch his son at the McDonald's All-America Game -- and, by the looks of things, he couldn't have been happier to do it!!

Two days after losing to the Bulls and one day before the two teams play in a rematch in Chicago, LBJ got away from his LA teammates for a night to catch Bronny James in the prestigious All-Star game in Houston, Texas.

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The King had courtside seats for the 18-year-old's big night ... and you can tell, he was thrilled to watch his son in the event on his night off.

Bron, who himself played in the game in 2003, took selfies with his family in their floor seats -- before celebrating every big bucket…