How should i tell my brother hes too nice?

i understand him trying to be a better person by being generous but in no way should he have given out that much money to a girl that you and him don't agree on. tell him you're happy that he is giving back and helping people, that it's really, really nice of him but you don't wanna see him get taken advantage of. if he wrote a check and helped this girl get a job, he's likely to do it again to one of her friends. if you feed the birds, their friends will come. so just keep an eye out for other people looking to take advantage of his kindness