"I can't come over because--"

At this point I shushed my 4 year-old, because the end of the sentence was going to be "because you're too mean to my little brother."The kid he was talking to was standing across the street with his mom, and my son asked if he could go to that boy's house. I said no, because the boy was consistently and terribly mean to my son's younger brother (2.3 yo): mocking the way he speaks, calling him a baby, pushing him away from playing with the "big kids" at the playground, etc. (my 4 yo got it immediately-- he knew what I was talking about and agreed that this boy was much meaner than his other friends, who are sometimes willing to include the 2yo, and/or don't go out of their way to make him feel unwelcome).On the one hand, obviously I shushed him, and explained to him that it's rude to shout across the street. In reality, I was a little embarrassed from the mom. She's nice enough, she thinks her son is "rambunctious," and if confronted with how he treats my 2 yo she'd probably say something like "boys will be boys."But should I have stopped him from telling the real reason I wouldn't let him play with the other kid? Why should I feel embarrassed that kindness is a parameter as to whom I let my kids play with?Hope this is making sense. I'm mostly confused, and looking from outside opinions as to this disparity between what I teach my kids, and what I consider "polite" to express. via /r/Parenting https://ift.tt/3019f6r