How do you truly get the adoption ending in Silent Hill 2?

I have looked online. Treating Maria badly, looking at Mary's picture and keeping one's health high does not work. Also, it has nothing to do with how many times you have been through the game. Because my first time getting the adoption ending was my first time through the game.

Memelord Prime2018-08-23T01:00:16Z

The various wikis and guides also mention listening to the headphones and the hallway conversation at Lakeview Hotel.

Other guides suggest it's the easiest ending to get and the one you'll probably get if you don't do anything special in particular.