I remember conversations about closing the bedroom door at night, but never spent time figuring out whether it mattered. Turns out that it can be the difference between life and death. (Wonder how many doors are left open for the pets coming to and from their person’s bed?)
https://thestir.cafemom.com/parenting_news/217560/fire-sleeping-door-closed
Parents: This Is Why Kids Should Never Sleep With Their Doors Cracked or Open

Many kids have specific bedtime routines each night that end with either mom or dad leaving their bedroom door either cracked or completely open. Although this might help little ones sleep through the night better because they feel less scared if monsters come out from under their bed or that their parents aren’t too far away, this actually isn’t the safest sleeping arrangement. That’s why one fire department is speaking out to warn parents about the importance of completely closing their kiddos’ bedroom doors at night.