Farnoosh_Torabi says:
A: Family members who mooch are the toughest to discipline. Next time you pick up your bro-in-law head to the pump together. That’s a smart time to discuss how your tank bill is soaring, not to mention how the commute is killing your car. Physically seeing you fork over money and hearing you vent will hopefully trigger him to chip in. Yes – it’s a bit passive aggressive, but like you said, he’s family. If he still doesn’t get the picture, ask him for a favor – to relieve you every other week by taking his car. The key is to make him feel like a big help and to ask in the appropriate context – not at Thanksgiving dinner when you’re tipsy off adult beverages.