Care and Feeding is Slate’s parenting advice column. Have a question for Care and Feeding? Submit it here.

Dear Care and Feeding,

My mother-in-law, “Diane,” has a history of disregarding my wishes when it comes to my two kids, who are 5 and 3. These transgressions have ranged from allowing them to stay up past their bedtimes to permitting forbidden foods. But what she did recently crossed a line.

Last Friday, Diane was supposed to pick the kids up from daycare and bring them straight home. Usually, they’re home by 3:30 p.m., but 3:30 p.m. came and went. At 3:45 p.m., I called her and it went straight to voicemail. I left a message asking her to let me know when she’d be home with the kids. After another 15 minutes, I called again. I left another message. By 4:30 p.m. I called my husband. He tried to get ahold of his mother too, also without success. At 5:30 p.m., when neither of us had heard anything from her, we were about to call the police when Diane finally pulled up.

She had apparently decided on a whim to take the kids to see the new Minecraft movie, and she’d put her phone on airplane mode, she said, because they were in the theater. When I told her how my husband and I had literally been moments from calling the police, she accused me of being a drama queen. I told her she was not going to be taking the kids on any more outings, to which she said my word wasn’t final because the kids were just as much her son’s as mine, and left.

While my husband was initially angry with his mother for not letting us know where the kids were all that time, he says she “meant well” and thinks I’m being too harsh (he also pointed out that we need her help picking them up from daycare and watching them until we get home from work). When I reminded him that we had been on the verge of calling the police to look for them, he said in hindsight he felt it was an “overreaction” since we knew they were with her. I spent two hours beside myself because I didn’t know where my kids were! As far as I’m concerned, if it means we have to hire a sitter, then so be it. Diane needs to learn a lesson here that what she did was completely unacceptable, don’t you think?

—Terrified for Two Hours

Dear Two Hours,

I do think that what your mother-in-law did was completely unacceptable, yes. But I also think you bear responsibility for what happened, too. If Diane has a “history” of doing whatever she wants to when your very young children are in her care, and you have continued to allow them to be in her care (and not just let her be their caretaker occasionally but counted on her—expected and “needed her”—to be), you’ve given her the message that, at the very least, you’re willing to put up with her shenanigans. Even if you’ve scolded or complained to her (have you?—you don’t mention that) about her past transgressions, you haven’t made yourself clear.

Help! My New Boyfriend Couldn’t Be More Different Than My Group of Friends. It Spells Trouble. My Daughter Hates Attention From Strangers. But Then She Goes Outside Dressed in Very “Eclectic” Outfits. Help! I Made It Awkward With a Colleague. Now I Want to Make It Worse. Help! My Mom Is Staunchly Against My Engagement. Her Reason Defies All Logic.

Diane seems to be a piece of work who enjoys irritating you, ignoring your guidelines, and being mischievous (the latter, perhaps, for the sake of being “fun Grandma” and courting favor with the kids). And the childish way she responded when you called her out on what she’d done, once she crossed your invisible line, suggests that she has no respect for you. She doesn’t seem like the kind of person you can give a pass to. Your husband’s siding with her isn’t a great sign, either. I think you need to have it out with him.

But don’t waste your breath on Diane. I’m afraid you can’t have it both ways: expect her to be your unpaid sitter, knowing that she has no interest in following rules (or even basic courtesy), and then getting furious at her when she escalates her usual casual disregard and disrespect to the next level. Get a sitter for your kids. Don’t let Diane take them on outings (or innings, for that matter) without you. Maybe she’ll get the message and come to you penitent after a while, begging for another chance and promising to abide by your rules. I wouldn’t hold my breath, though.

—Michelle

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I’m a single mom and my daughter is 4. She’s bright, funny, generous, and headstrong. Like most 4-year-olds, she occasionally cops some attitude, like shouting, “Everyone stop talking!” when she wants to say something. Sometimes she melts down into a sobbing mess in response to setbacks or difficulties, but I think this is pretty normal. I don’t love it, but I accept it and we deal with it as best as we can. I’m pretty sure I’m doing this parenting thing all right. The problem is my mom and sister.