Kidalex is legitimately just a kid. It should be hard for OP specifically to comment on his behaviour given Alex is not much older than Zach, and both of them are hormonal, roostery, mentally deficient and haven't had social graces beaten into them yet.
Be the bigger man and pay no attention to him, Zach. Take it from me that it's not worth your time to pick fights with every drooling handicap who slips on through the bar doors.