Dear Prudence: Starbucks seasonal tumblers are causing me major family drama.

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Dear Prudence,

I love my 12-year-old stepdaughter “Stella,” but she would lose her head if it wasn’t attached to her head. She is constantly losing items or forgetting them or misplacing them. Despite living only 10 minutes away from her mother, it is always a struggle to hand Stella over because something she has to have gets left behind. We tried lists and alerts on her phone but short of packing everything for Stella ourselves, something ends up lost. Right now, Stella and my own two daughters have a mild obsession with the seasonal tumblers from Starbucks. They take them everywhere, but unless I literally carry it for Stella she loses it. Even on sale, they are expensive. After Stella managed to lose three over the course of one weekend, I hit my limit.

I bought a huge supply of bottled water and put it in the fridge for Stella. She can take that when we go out. Stella is embarrassed by this and complains to her mom. Her mother accused my husband and me of “favoring” my girls over Stella. At this I told my husband that unless her mother buys the tumblers for Stella, it is over with. I love Stella but this has gotten ridiculous. Is there any other way?

—Forget

Dear Forget,

Where is your husband when the packing, handing over, tumbler shopping, and weekend activities are happening? Why is tumbler monitoring your jurisdiction? This is clearly a contentious situation in ways that go beyond Starbucks merchandise. And Stella, a child of divorce who is having to go back and forth between homes and families, is obviously struggling. So step back. As a stepparent, you know you have gone too far (and done a job that isn’t yours) when you find yourself trying to fix a child’s shortcomings and making them suffer when that doesn’t succeed.

Don’t get me wrong, there is nothing wrong with refusing to buy endless expensive and unnecessary mugs. Nothing at all. It would be reasonable to decide, for example, that you buy one girl a tumbler each holiday, or each month, or five times a year, or whatever. But “I buy them endlessly until I lose my patience and then never again” isn’t a clear or fair policy. By getting so frustrated at how “ridiculous” Stella is and acting as if she never deserves another tumbler in her life, you’re making this situation more emotional and punitive than it has to be. Your response could have easily been “Oh no, you can’t find yours? Well I’m getting everyone a new one for Christmas. Remind me what color you like and I’ll make a note.” Treat all three girls equally. Decide what your limits are. Kindly and gently stick to them. Let Stella’s actual parents decide how to proceed. Perhaps the plan will include an exploration of what’s behind her absentmindedness, and whether she might need more support to manage her belongings and (probably more important) her place in the family.

I’m a 23-year-old college grad looking forward to graduate school this fall. I’m writing because I’m puzzled by my mom’s behavior, and worry I’m being uncharitable. I’ve always had wonky teeth, and my mom took me to visit a new dentist—an appointment for which she was present.Things were grand until the dentist kissed me, through his mask, on the forehead mid-exam. This was done openly and obviously, and I was too shocked (and silenced by the hand in my mouth) to say anything. My mom witnessed this and said nothing. I was willing to consider it an unconscious slip-up when, near the end of the visit, he again kissed my forehead, this time without a mask.