It was implied that Shouzou knew his son wasn't dead because of how Yamato was acting which implies that had he died very bad things would happen and the fact she looks identical to someone Gunzou was close to it is clear she doesn't want him dead.
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Higurashi: Its a bit like watching a trainwreck, except you keep getting to see different trains wrecking with roughly the same passengers, into a variety of different objects. Also, the trains are driven by monkeys. On LSD.