I'm going to refuse to drive my brother and his girlfriend to and from a party.
Why don't you want to drive them?
It's a free country, I don't have to do it.
If you aren't doing anything maybe you should do that favor for them. Its better than them getting into an accident or drinking and driving.
I just really don't feel like it.
I just think it's nice to help siblings out with drives if you can. Maybe he'll repay the favor for you someday?