I'd give my life to save my brother, and homicidal would be a polite way of describing my thoughts if someone were to hurt him.
I wouldn't however waste my time training my brother if he routinely slacked off.
The older you get the more you realize time is precious. It's like land...they aren't making anymore of it.
Family or not don't waste other people's time; it's one of the rudest things you can do. No one owes you their help.