Head to the NERO refugee Camp where Sarah’s tombstone is located. There are several freakers in the initial area so it’s up to you if you want to sneak around and deal with them so you can freely pick up the loot scattered around. Sarah’s memorial stone is just past the SUV crushed by the fallen tree trunk so you have to circle around to the left so you can push the SUV later on.
Circle around the MMU to the southwest and exit through the opening on the fence behind it. Continue uphill to reach the helicopter landing zone area of the refugee Camp. There are a lot of freakers patrolling the area and you’re required to kill all of them so it’s recommended to deal with them silently to avoid getting overrun.
After killing the last Freaker in the landing zone, approach Sarah’s memorial stone to trigger a cutscene. Once the cutscene is over, the mission will be complete. Since you’ll be visiting Sarah’s memorial stone several more times after this, leave the area by pushing off the SUV under the tree trunk. This way, you just need to go straight to the memorial stone from the entrance.
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