leave it be(allow something to follow its natural course) verb
let it be(leave something to follow its natural course) verb
let nature take its course(permit events to proceed without intervention) verb [UK: let ˈneɪ.tʃə(r) teɪk ɪts kɔːs] [US: ˈlet ˈneɪ.tʃər ˈteɪk ˈɪts ˈkɔːrs]