Thank you for the responses.

I'm not sure what kind of family intervention we can do. Mom has already voiced out her opinion about his habit and the conversation didn't become an outright argument but sure wasn't a good one either. And Dad has been long gone so he won't be of help, even if he would've wanted to.

Dropped by his place earlier and found him nursing a very bad hangover. Seems he missed work. A neighbor told me he haven't been seen my brother outside for two days already. I have this feeling that things aren't as 'OK' as it actually looks. Might post again if something turns up. Again, my thanks.