Re: batameez younger sibling
Tell them that you understand that they are likely going through yet another phase but they need to smarten up and act like they are contributing members of the family.
The more you allow their behaviour to irritate you the more you reinforce that they are accomplishing something with it.
If they yell or talk back, ignore them. The louder their voice the softer yours' should be. If they mope, sulk and have an air of just plain attitude reach out ONCE and let them know that if something is bothering them you care there for them. But that's it. Don't molly-coddle.