Citizenship through Great Grandparents?

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I was wondering if it is possible to get citizenship through my great grandfather/grandmother on my father's side (father's mother's father/mother). My patrilineal grandfather naturalized before my father was born, so I can't go that route, however my grandmother was born in the United States as an American citizen before moving back to Italy for two decades and then returning. As far as I know, her parents never became American citizens or renounced their Italian citizenship because they stayed in Italy. Could I go through either of them to get citizenship? Thanks!