Stock image of teenage girl eating cake.Photo: Laura Beach / Getty Images

The arrangement has gone smoothly until a recent incident left OP confounded.
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Stock image of a bread box.Courtesy of Getty Images

Courtesy of Getty Images
OP’s sister wasn’t happy that Carly helped herself to the cake. “My sister said that she should’ve asked before helping herself to the cake, and that it was expensive. I apologized to my sister and told her that I would have a word with my daughter.”
While OP thought that was the end of that, her sister continued, “She mentioned again that the cake was custom-made and expensive and says that we should be compensating her.”
“At first I honestly thought she couldn’t be serious, but she did want me to give her money because of the cake. I mentioned that surely the cake was going bad soon if it wasn’t already stale (I said this light-heartedly, trying to lighten the mood) but made it clear I was NOT GIVING HER MONEY,” she explained. “She says she paid €70 for the cake and she expects me to give her €20. I told her I’m not doing that.”
“My sister says I’m being inconsiderate and that my daughter ate the slices without permission. I feel like she is being petty, and what difference would it have made if all of it got eaten last weekend or at the birthday party?”
Stock image of woman taking euros out of her wallet.Getty Images/Brand New Images

Asking if she was wrong, a few commenters asked for more information, at which point OP revealed the cake “wasn’t frozen, it was being kept in the bread bin.”
“The cake was being kept at room temperature in a bread box on the counter. After two weeks, it really wasn’t even a viable edible item anymore, let alone one with monetary value,“one commenter said. “Your daughter is lucky she didn’t get food poisoning.”
Stock image of a slice of cake with the cake in the background.Jamie Grill/Getty Images

Jamie Grill/Getty Images
“And don’t bother to give sister a heads up. She can find out your daughterwillbe charging her, oh, shall we say, 20 euro an hour? For every hour? Or whatever the going rate is, or she can scramble to find an alternate. Your daughter could make all kinds of money for her Starbucks addiction, working for somebody else. But the bargain sis had- ended when she expected you to fork over 20 euro for stale leftover cake.”
source: people.com