If something is worth fighting for, then it's worth fighting for
OK, Jr. stepped in front of Pain, with a 'don't even think it' look. And good for him, too! And now his mother ordered him to step aside, and he didn't. Again, good for him.
But it's easy to just stand there and look defiant. (Well, maybe not all that easy if you're trying to stare down Mandy!
). But something is always more valued if you pay good, hard coin (whether that be actual money, or instead blood, sweat and/or tears). So, whether Mandy intended it this way or not, should Jr. stand up to Mandy, win or lose he's made a statement much louder than mere defiant interference.