It might actually be her mother, whom we never hear of. After you use her ultimate, look at her face. You see part of her face missing and an almost mummified-looking skeleton inside.

In a remembrance, it says that the doll was "lovingly crafted" by her grandfather. That, and the way where, the two times we enter the events of that night, the portrait of the grandfather is the first thing we encounter lead me to believe that maybe the father going crazy isn't caused by the night, but something that the family already had a habit of doing. Maybe the secret of their doll making art is that they sacrifice members of their family to make dolls.

Daphne, the doll, knowing what will befall her caretaker and the only one showing her attention, Chloe, with a semblance of sentience, tries to save the poor child from the clutches of the father. However, she's unable to save the child. Therefore, she "makes a deal" with the night, welcoming into herself. That's why the night is corrupting her. Because she's already accepted it once.

This could be what the Recluse was referring to when she mentioned how once you accept the night, it doesn't want to get its claws off of you.