The dark room

The brothers Samer and Siraj stand in front of the room's blue door, conversing: Samer: I will never enter that room. Siraj: Why is it closed, brother? Samer: It has been closed for years... And my mom and dad don't use it. We have real and false fears in our lives, the keys to which are caution and boldness. What is the secret of the dark and locked room in Samer and Siraj's house?