he that lieth with dogs riseth with fleas

proverb If one spends time with bad people, one will suffer in some way (often by becoming like them). I worry about my brother hanging out with all those troublemakers—he that lieth with dogs riseth with fleas. I'm a firm believer of "he that lieth with dogs riseth with fleas," so I don't trust anyone who hangs out with that slimy politician. A: "Why has my reputation taken a hit? I wasn't involved in their crimes!" B: "It doesn't matter—he that lieth with dogs riseth with fleas."