She was angry about my not returning her deposit, so she posted in a public forum that I didn't take the kids outside all winter (I have an email from her in January where she thanks me for taking the kids outside so much), that I didn't warn her about her son's behaviour (I have dozens of texts that prove otherwise), that I refused her receipts (I issue them yearly and she has hers), and that I was overwhelmed with too many kids, claiming that I had four children under 18 months (complete lie). It was embarassing as heck. My current clients saw it, too, and they knew right away that she was full of it.

She clearly could have cost me my business. I live in a small town.