Towards the end of Life is Strange 2‘s second episode, Sean and Daniel will want to look through Karen’s room to try to find out more about their estranged mother. However, finding the key to unlock the room’s door can be a bit tricky, especially since the game throws a red herring your way.
Upon attempting to open the door to Karen’s room, Sean will discover that it is still locked. Then, the camera will point in the direction of Claire and Stephen’s room, implying that this is where you should search for the key to Karen’s room. But this is just misdirection. Feel free to look through Claire and Stephen’s room anyway if you want, so that you may find some pieces of environmental storytelling, but to find the right key, you’ll want to go into the bathroom in between Claire/Stephen’s room and Karen’s room.
Once in the bathroom, Look at the Dirty Laundry next to the sink. Once you’ve done so, you’ll be able to Look at the Cardigan hanging over the laundry hamper. After you’ve Looked at the Cardigan, you’ll be able to Search it, which will result in Sean finding the key to Karen’s room. Now you can progress through the rest of Life is Strange 2‘s second episode.