This olympian made sure that the sacred home fire on mount olympus never went out

Hestia was the Olympian who made sure that the sacred home fire on Mount Olympus never went out.

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     Hestia was the answer. She was an Olympian but, when Dionysus became an Olympian she gave up her throne on Olympian Counsel for him to keep balance. So, it's was the Olylmpian, not is the Olympian. She still keeps the hearth going though but now she is just a godess, not an Olympian.