I was recently informed I'm being promoted to Manager of a small municipality following the typical resume/interview process. One of the other final candidates is also an employee, with MANY more years employed here. Let me say, since the announcement, you couldn't cut the tension in this office with a chainsaw. I am trying to give her some time to process all of this, but I can't and won't work with this type of tension and stress.
My plan is to give it a week or so (maybe less) and have a one-on-one talk with her. Reiterate that she is a valuable employee and is needed (which has been done already also by current manager). Frankly, I need her assistance. She does have a wealth of knowledge on some aspects of municipal gov't administrative functions. For a quite an amount of time, too much was piled on her leading to a variety of issues that reared their ugly heads. The current Manager had taken a step back to focus on his new endeavor and was basically remotely managing. She was given a raise with the expectation that she was taking on a bit more assignments, none of which entailed managing, but were administrative in nature. What you have left is the bag that I'm walking into with officially being promoted which takes affect later this month.
I've been in this position before in the law enforcement world, but that had a chain of command, and being promoted over less senior employees wasn't as dramatic (in my opinion at least).
If anyone has advice as to how you handled a similar situation, feel free to offer it up. I'd be glad to hear it.