Succession season 3, episode 5 showed a deteriorating Sandy Furness amidst a tense shareholders meeting, but despite rumors of syphilis, the actual medical condition of Logan Roy's arch-rival is still a mystery. It's possible that Sandy did, in fact, contract the sexually transmitted disease, but that seems like just the type of disparaging gossip that the catty Roys would stir up to create ill-will towards one of their enemies.
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