I call myself a "Mommy Stage Manager," which is ironic, as I never intend to have kids.
I take care of people. I make sure that everyone has what they need to do their jobs, and that they know they can come to me if there are any problems. This isn't just cast, but designers, directors, and crew, as well.
Sometimes what someone needs is a walk outside with someone to listen to venting, a piece of chocolate, a hair tie, someone to go to bat for them with someone else, a reminder not to forget their cell phone, or even a swift kick to the pants or to be left alone to sulk in their room. And I can provide all that. I find myself adapting my role, not just from show to show, but from person to person in any given show.
Also, as "Mommy," I'm ALWAYS the one who just rolls her eyes and goes for the figurative paper towels when everyone else is crying over the figurative spilled milk.