After bringing home my newborn from the hospital, I was shocked to find a $600 invoice on the kitchen table, supposedly from my mother-in-law, Abigail, for caring for our dog, Rich, while I was in labor. My husband, Jake, had promised to handle it, but I was ready with my own plan.

A few days before my due date, I had asked Jake about arrangements for Rich while we were at the hospital. He assured me his mom, who loved Rich, would take care of him. When we left for the hospital, Abigail seemed happy to help, though I sensed she wasn’t thrilled about not being allowed in the hospital room.

Labor was grueling, but after three days, we were discharged and headed home, eager to reunite with our dog and baby. That’s when I found the invoice, with Abigail demanding payment for feeding and walking Rich. I was stunned; she hadn’t mentioned any charge. I decided to take matters into my own hands.

When Abigail visited to meet the baby, I presented her with a folder detailing past favors Jake and I had done for her: moving her house ($800), covering her car repair ($1,200), and babysitting ($600). I pointed out that family doesn’t charge family. She was livid but couldn’t argue. She stormed out, and Jake, impressed by my move, laughed and hugged me.

Though Abigail likely didn’t learn her lesson, she wouldn’t be seeing that $600 anytime soon, and I’d be ready if she ever tried again.