There's a common saying, "You get what you pay for." People usually use this when they're talking about a cheap item they purchased that ends up breaking or otherwise being subpar. It makes sense. If you buy "AirPods" on Temu for $19.99, you'd be the fool for assuming they would connect to your phone. If you pick up gas station sushi for $4, you can't be that surprised when you spend the rest of the night hugging the porcelain throne. But does the same thing apply to family? If a family member offers to do something for free, are the expectations equally lowered?
There's another expression that's helpful here: "Beggars can't be choosers." So, if free babysitting from your sister is your only option, you can't be offended when she doesn't show up after you slighted her. She's not your employee after all. That's exactly what happened in the following story, where a stealing accusation led to some pretty dramatic events.