Behind the door

I'll find you

I let my search off for a few days to calm myself a little. But the cops couldn't find anything so I stopped relaying on them from now on. The first thing I thought of is going through her diary again. And once again the diary wasn't at the place it was the last time. I found it on her table with a pen next to it. Like she was writing it in a hurry. And the pen was covered with blood. I didn't care so I just opened the diary to see the date 24th December 2022. Which was today. I took a quick glance and found out she finally wrote something that stands out. She wrote "I'm scared for my sister's life... I hope she never finds out the hidden door in the room. I hope she still believes I'm dead.. It's safer this way, for me and for her.." I was confused. I looked at her room more than my own. I have never managed to find a "door".. What does she mean by it's  safer for me.. AND her? What hidden door is in her room? That question has been in my head ever since I read that. I don't understand... Is Kayla alive? If she isn't.. how is she still able to write in this diary everyday..? Is she a ghost? All I knew is I had to find that hidden door. Even if I was warned not to by my sister.