I wouldn’t say this if he was younger, but kick the fucker back.

Where the hell are his parents?!? They need to discipline his a$$.

At 12, his balls should be kickable and he'll be susceptible to grown-man pain. You kneed to get revenge.

You know he's going to do it so prepare yourself. hopefully him hitting the guard on hurts like hell. Accidentally get him in the gonads and see how he likes it.

I'd say hit him in his balls every time he does it to you. Not full force, but tell him, "You do that again and I'll hit you back." It's the only way kids like that learn. If he doesn't learn, he's going to do it to the wrong person and get the sh*t kicked out of him.

kick the shit out of him. he's old enough!

He kicked you in the nuts and it was "fair and square"? What the hell were you doing?

Give the kid a nice kick in the balls. He’s 12 years old, so he should know better

Take away his phone or something he loves for ever time he’s done it and if that doesn’t work kick him back until he promises never to do it again

I feel like it’s important to point out that “fair and square” means you got what was coming for you. Either you chose the wrong idiom, or you did something to deserve being kicked in the balls.