According to its Case File Granny is Slenderman's mother-in-law.
Pre v15.0 it used to spawn in the Teleporter Room before Pinhead took the location.
Be careful about Granny's bear trap in Endless Survival at higher waves because killers can swarm you easily when trapped.
Granny plays its jumpscare sound when you are in its sight, listen closely to know if it's about to sneak up on you.
In Area 51 Storming, at the end of the last wave, be aware, as it always spawns a beartrap and most people with low health ended up there.
If you are Granny, put your bear traps on small entrances like the entrance to the cubical loop.
Be wary of Granny's bear traps, they are quite hard to spot and can spell doom for you if you accidentally step on one of them with low health or being chased by a killer.
Granny is extremely slow and has a tall hit box, so it can be easily killed with any weapon.
Said trap is a single use stationary hazard that will deal damage and stun the player for 4 seconds upon activation by the player. Granny will randomly select a spot (unless controlled by a player) to place a bear trap. This is often benefited by its bear traps and its location with tight corners and little maneuvering room. Granny is slower than the average killer, however, it deals a considerably amount of damage. Upon noticing a player it will play a jumpscare sound before chasing the player. Granny is a tall elderly woman with grey hair, it wears a long white dirty dress and has a distorted face with rotten teeth and blank eyes.