based on what other people have said you dont need to keep an eye on freddy, you just need to listen for 5 of her giggles then wait 20-25 seconds after the 5th then close the door until you hear her giggle again
Freddy is timer based. I was playing with stopwatch to get 4/20 and she appears always at around 7:42-7:45 of night so I was closing door at 7:38 just to be safe. Open doors after hearing laugh and you’re done for night