Not sure if this qualifies as a parent story - but it is certainly unhinged...
A parent got one of the highly competitive TA jobs at my DC's primary school. It's an 8-class school (single year intake, plus 1 bulge class). She had DC in 2 of the classes.
She has an affair with one of the Dads. Both leave their parters. Gets very messy between her 2 children and his 2 children, all of whom are at the school. It's decided she will not work in the 2 classes with his children and one child is moved to a different class (bulge year).
Has another affair with another Dad. This time Dad stays with wife, but now there's a 3rd class she can't work in.
This has all happened with the 2 academic years since she joined the school. Meanwhile the school is sending out vaguely worded letters asking parents not to speculate on HR matters which, naturally, just fuels speculation and makes things worse.
She is moved to another class, which happens to be taught by her close friend (two of their DC are also best friends). She is now single so teacher/close friend invites her and her DC to join her, her DH and their DC on holiday. You can probably guess what happens next: she has an affair with the teacher's DH. My DC had left the school by this stage, but the teacher was signed off with stress and they eventually sold the family home in the village and moved away (I think her and her DH eventually got back together).
4 years on from this, and the TA is still at the school.
All I can say is, she must be one hell of a good TA to make up for all the HR issues she's caused!