Emily Yoffe, aka Dear Prudence, is online weekly to chat live with readers. An edited transcript of the chat is below. (Sign up here to get Dear Prudence delivered to your inbox each week. Read Prudie’s Slate columns here. Send questions to Prudence at prudence@slate.com.)

Q. Daughter’s Trust vs. Public Service: My daughter goes to a dance class where the dance instructor’s son also gives lessons. He’s about 25 years old, married and with a kid on the way. My daughter told me that when they were in the tour bus the son asked one of her dance-mates if she’d let him kiss her. This girl is about 15 years old! She told my daughter she felt she couldn’t say no, so she let him. The girl feels bad, but doesn’t want to hurt the wife (who’s been there for some of the performances) nor does she want to break up a family. My daughter told me this in confidence and made me promise I wouldn’t tell a soul. If I tell this young girl’s parents (who don’t come to performances and who I’ve never met), my daughter will lose all trust in me. (My daughter’s trust is essential because if this happens to her, I need her to trust in telling me.) If I don’t tell the parents, I will be allowing this man to continue to surround himself with these girls. I don’t know if this is the first, or one of a long list. What do I do? I’m already taking my daughter out of the dance school, but I can’t imagine leaving her friend behind to fend for herself.

A: Your daughter did the right thing by telling you. Now you have to tell her that you have to do the right thing yourself and report this. You explain to her there are some confidences that can’t be kept because they reveal that innocent people will be hurt—likely very badly. Because this is so sensitive, you and your daughter could go to a lawyer together to have a confidential conversation about how to best proceed—whether telling the parents only, or the parents and the police—and also clarifying what all this will mean for your daughter. Maybe this kiss was the first (I doubt it), but it won’t be the last. This guy is in pole position as a dance instructor to teenage girls to pick off the most vulnerable ones. He’s not going to stop with a kiss (and even if it’s just kissing, this should be something brought to the attention of law enforcement). Yes, this will be messy and ugly, but messier and uglier will be allowing this pervert to get away with years of abuse. You need to make clear to your daughter that you will be there supporting her every step in this process, but that it must move forward because she has found out about a crime. Also tell her that while her friend may have confessed in confidence, she made the confession because she’s being pressured and doesn’t know what to do. What has to be done is that responsible adults step in and make sure this guy is stopped.

Q. Holiday Leftover Etiquette: I have a dispute with my mother-in-law. She hosts many holidays at her house and all of us bring side dishes while she makes the turkey. On Thanksgiving my mother came and brought a dessert. At the end of the evening she noticed that it was barely touched so she wanted me to take it home. My wife received a call from her mother seriously vexed that everything was not left at her home. When I host, I have no problem with people taking back things as it is usually a massive amount of food that would go to waste if it remained (as was the case here). What is the proper etiquette of potlucks?

A: Clearly your mother-in-law had her eye on the pie. The food you bring to an event becomes property of the host. So yes, your mother was somewhat out of line to send her dessert home with you without checking with the hostess. At potlucks there usually is plenty left over and the host often divvies it up, but not your mother-in-law. However, this round-robin of recrimination is the ultimate in silliness. Your wife should have told her mother she’s sorry she took home a dessert her mother wanted to keep—but should have defended your mother’s innocent behavior. If your mother-in-law is hosting Christmas this year, now you know not to take home a doggie bag.

Q. A Tragic Situation: My wife’s mother was killed by her boyfriend “Bob” 30-odd years ago from a house fire which he started. He was a drug addict and served only a short sentence due to young age, mental health issues, and that he maintained he thought he was setting fire to an empty house. We discovered Bob has totally turned his life around and is now working as a teacher. From what we can gather he is a well-respected family man and has two children. My wife lost it, saying he did not deserve to live a clean, decent life after causing so much damage in hers. I am pretty sure he has hidden his past as he was also accused of attempted murder of a child (my wife) even though he was acquitted. My wife wants to publicize Bob’s past to his family and work. I am worried about her revenge crusade and a part of me thinks a man who can turn his life around so remarkably deserves to be left alone. I am unsure how to stop her and support her emotionally at the same time.

A: This is indeed a tragic and wrenching situation that has left an understandable shadow over your wife’s life. But I agree with you that seeking revenge in the way your wife suggests will not bring her peace but just the opposite. Bob went through the criminal justice system and even if his punishment was inadequate, he served it. He has turned his life around. It may be that a social media campaign by your wife will cost Bob dearly. But it will cost her, too. There will be plenty of people who attack her and find her vindictive, and she will end up reliving the worst moments of her life over and over. Please support her by offering to go with her to a therapist to talk all this out. She needs enduring support. Even traumatic events that have taken place decades ago can rear their heads in unexpected ways, as this has for your wife. What happened to your wife cannot be undone. But with help she can accept the past and not allow it to undo her present.

Q. Re: Daughter’s Trust: You’re right of course, Prudie, but does the daughter really have to go to the lawyer? That seems to me to be the kind of thing the mother should handle herself as the adult, and she can pass on any info to the daughter. Taking the poor kid to a lawyer on top of (necessarily) betraying the confidence seems completely traumatizing to me.

A: She should talk this out with her daughter. It might help her daughter to be in a room where she knows the conversation is totally confidential and where she can ask her own questions and express her concerns. If she doesn’t want to do go, sure, the mother can go alone and ask the questions her daughter would want answered.

Q. Time to Move On?: I have been with my wonderful boyfriend for over three years. He has hinted about proposing in the past but has never actually gone through with it. I moved to a new state to be near him, then to his city after I completed graduate school. He knows I want to get married and I have tried discussing it with him. He worked an extremely demanding job with grueling hours and I stood by him. Now he has a better job and we are able to spend more time together. Recently, I became frustrated after watching so many people I know who have been in much shorter relationships get engaged, and I wrote him a six-page letter stating that I didn’t want to force him to get married but felt misled by his hints. I asked him to give me space. He was devastated and revealed that he had bought a ring and was planning to propose just days after I wrote the letter. Now we’re both really upset. I feel that if he had just proposed earlier, I would never have felt the need to write the letter. He feels I didn’t trust him and is now holding back on proposing. We really love each other but I feel that if he’s still not sure about me after more than three years, sadly it may be time to let him go. How do we move forward?

A: So, what does the ring look like? I assume he showed you the rock he is now withholding, just as a matter of good faith. Or maybe he’s hidden the purported ring, just to punish you for having the audacity to express your desires about your joint future. This is an O. Henry style stand-off: He was ready to propose, then you ruined it by asking him to propose. I’m going to assume your six pages (six pages!) were not a screed against him, but a cri de coeur. In that case, someone who wanted to marry you would have read the letter, gotten the ring box, and said, “Here’s my answer.” Good that you’re not beating yourself up for supposedly blowing his proposal, but are more uncertain than ever about your future. So you make your own. Follow through on your plan to get some space to think about things. You’re right, three years is more than enough time, and now he’s manipulating you—a decision about getting married is a joint one, not the man’s alone. So spend some time alone—and even with other available men—to see more clearly what you want out of life.

Q. Can’t Give Legal Advice: I’m a third-year law student at a well-respected school. When people find out, they often ask me for legal advice, especially about my area of specialty. I explain gently that I’m not an attorney and that I can get in big trouble for appearing to give legal advice, and if I know a good attorney specializing in that topic, I can offer a referral. This response often doesn’t work. Folks seem to think I’m being a snob or a jerk for refusing to help them (for free), or they keep trying to reframe their question to “trick” me into answering. It’s quite uncomfortable. Any suggestions for how to be firm but kind, while living up to my ethical and professional responsibilities?

A: Counselor, you better get used to abiding by the tenets of your profession now. For you that means not giving legal advice because right now you’re not a member of the bar. And even when you are, giving legal advice is presumably something you will want to do in exchange for money. You have entered a profession in which you are going to go up against others who are going to try to use tricky arguments to counter yours—so learn how to hold your own. It doesn’t matter if people asking for free (and illegal) services then declare you’re a snob or jerk for not providing them. You just stick with, “I’m sorry, I can’t answer that question. But I’m happy to give you the names of some people who can.”

Q. How to Get Someone to Follow Through?: I have a great boyfriend who has been living with me in my home. If I ask him to change out a light bulb, for example, he’ll readily agree ... and then never do it. I hate to be a nag, but after the second or third weekend of reminding him that he said he would do it, I just end up doing it myself (which I realize teaches him that he really doesn’t have to do it, but it’s dark in that hallway!). However, if it’s a bigger thing that I can’t do myself, I’m kind of stuck. We’ve talked about his pattern and he always apologizes and admits fault, but then it’s right back to same ol’, same ol’. Um ... what gives?

A: How many boyfriends does it take to change a light bulb? One, as long as you change boyfriends. There’s something fundamentally off with what you describe. Not just that this slug, who’s presumably taller than you, won’t get the step stool and change the hall light, but because you describe him as a kind of freeloader invading your home. But maybe he thinks of himself as a guest and is a little put off with being expected to do household chores. The two of you need to have a serious discussion about why you’re living together and what each of your expectations are. And for you, these expectations include his share of maintenance of your joint domicile.

Emily Yoffe: Thanks, everyone. Have a wonderful Christmas. Talk to you next week.

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