Fallout 4: Returning the Favor walkthrough

You'll find this quest at Abernathy Farm, south of Sanctuary Hills and west of Concord.

Talk to Blake Abernathy to accept the quest, then head northeast until you reach USAF Satellite Station Olivia.

Clear out the station of all its Raiders then search for Mary's locket. You'll find it in a toolbox indicated by a waypoint marker. Return to the farm and talk to Blake to complete the quest.

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