CNN  — 

LeBron James is upset after a fan threw something at his oldest son during his son’s basketball game.

On Monday, both LeBron James and LeBron James Jr., known as Bronny, had basketball games in Massachusetts.

LeBron James got to watch his son play in his high school game in Springfield before the Los Angeles Lakers game against the Boston Celtics later in the evening.

Bronny James is a freshman at Sierra Canyon, a private school near Los Angeles that has become a pipeline for future college and NBA stars. His team plays a national schedule and was facing Paul VI Catholic High School from Fairfax, Virginia.

During the game, a fan threw something at Bronny James, hitting him in the back while was getting ready to inbound the ball. Play was stopped briefly, and security was called over, but it’s not clear what was thrown.

After his game against the Celtics, LeBron James said he was sitting on the opposite end of the floor of his son’s game and didn’t realize what had happened until he later saw it on video.

“That (expletive) made me mad when I saw that,” LeBron James said.

Bronny James in action  at the Hoophall Classic on Monday in Springfield, Massachusetts.

LeBron tweeted a video of the incident, writing, “Hating has no age limit!” He followed that with the face-palm emoji and wrote, “#JamesGang is build for it and well equipped. As we proceed.”

“It’s just disrespectful,” James said. “It was a little kid, too. I don’t know how old that little kid was. I don’t know if he learned that on his own, or he learned that at home, whatever the case may be, but it’s just disrespectful. I wonder how old that kid is.”

According to ESPN, Bronny James didn’t talk to reporters after the game. Instead, Bronny James’ teammates spoke up for him.

“He never lets anybody faze him,” senior Ziaire Williams said, according to ESPN. “You’d be surprised all the stuff he has to go through. It’s not fair, you know. He doesn’t let it faze him at all. Really, I learned that from him. Honestly, he teaches me about that stuff, and he’s younger than me.”

Said LeBron James of his oldest son: “He’s a cool, calm – he’s better than his mom and dad, let’s just say that. He is. He’s better than his mom and dad for some of the things that he kind of lets off his shoulder. Well, I guess he’s taking after me because I let a lot of (expletive) go too.

“He’s a great kid, and most importantly he just loves being around his teammates, being a great kid, being a model citizen in the community, and playing the game that he loves to play, being a big brother to his brother and sister.”

Sierra Canyon went on to lose, 70-62. Later, the Lakers lost 139-107.

“The only bad thing about today is I took two Ls,” LeBron James said with a smile. “The James gang took two Ls today, but there’s always better days.”