We had an employee (FE) who resigned over a year ago and left in good standing, to move with her DH across the state. We promoted someone (CE) to her position from within, and all has been well since.
All was well, but three of the other employees of the same level as FE have been campaigning for FE to get her job back, only problem is CE is in the position, and is doing a great job. CE used to work in my office and is a great guy. Now, FE is moving back to the area, and there is much clamoring (by the current staff) for FE to have a position made for her, which is certainly not in the plans or budget.
So, while this is not traditional PD, I still nominate FE for a "sour grapes" kind of PD.
What is even more ironic, the main person campaigning for FE did the exact same thing 8 years ago, and has lamented the loss of her seniority ever since!