I am playing TWD on a first gen Ipad retina device (ipad3?) and when you have to sneak upstairs in the house to find items to help you with your wound I came a cross two ghost characters in two different rooms, watch the pictures.
I apologize for the inconvenience. Please try closing the app, and relaunching it while being connected to a strong internet connection to receive any available updates. Then rewind one checkpoint in the episode select menu, and you should no longer encounter this when you progress through this scene.