In a live chat, Prudie advises the sister of an underage girl making sex tapes with her boyfriend.

A: You don't have to ruin the relationship with the neighbor. You just have to call the number on the flyer, give your neighbor's address, and say she recently adopted a dog that looks remarkably like theirs. You must know what your neighbor's new dog looks like because she's been out and about with it, which means anyone in the neighborhood could have noticed. If the neighbor is contacted by the people with the missing dog, then comes to you with accusations, just say you don't want to get in the middle of a dispute she may be having with the owner of the lost dog.

Q. Childhood BFF Dating My Dad: At my 26th birthday my childhood best friend Corinne apparently hit it off with my 56-year-old, widowed dad. They enjoyed one another's company, grabbed coffee a few days later, and one thing led to another. Now they've been dating for six months, and their relationship has become serious enough that they've told my brother and me about it. On the one hand, I'm very happy that my lonely father has found someone he might love. On the other hand, no matter how much I tell myself that they're both grown, intelligent adults, I can't suppress the giant GROSS! that rises in me when I think of them together. I'm not sure how to handle this—and I want to handle this maturely—because I have so many different emotions and thoughts. What can I do to become more comfortable with their relationship, which is complicated by she and I being close in age and our past friendship?

A: I think you're handling it perfectly so far. You're right to be happy that two people you care about are delighted in each other's company. And given each of their relationship to you, and their age difference, it's normal that you also find yourself suppressing a gag instinct. Beyond that, you don't have to do much more than accept your complicated feelings. Since everyone is an adult, it will be best for your mental health to stay out of their relationship. It's likely that it will run its course and eventually Corinne will move on to someone closer to her own age. There's no reason now to start contemplating that your former BFF might one day become your stepmother.

Q. Sex Tapes: Remind your little sister that it's incredibly easy for those tapes to wind up on the Internet, and all it would take is a few minutes for the boyfriend to post them on porn sites. If she doesn't think he'd do that, think again, because clearly plenty of boyfriends and ex-boyfriends have done it. They might consider looking online to make sure he hasn't already.

A: So true. That's why it's important for the girl to get possession of the tapes. But it would be best not to terrify the younger sister, just to explain this could happen given the technology.

Q. Why Do You Think "Getting Through High School" and "Exploring Your Sexuality" Are Opposites?: I agree making sex tapes as a 16-year-old is not the best idea, but every teenager needs to be exploring his/her sexuality in some way, just as they are exploring every other important area of identity. That doesn't necessarily mean having intercourse, but being a sexual person doesn't mean you're going to flunk out of school!

A: And kids in nursery school are exploring their sexuality. I am not against this exploration—it's fun! it's natural!—it's just that teenagers can find themselves going further than is good for them. I think making sex tapes indicates this girl would more productively have her head inside a textbook.

Q. Their Friend Stalked Me: Last August a classmate named Greg began stalking me. Eventually Greg's stalking led to his expulsion from our university. He told his friends he was leaving college because I broke his heart and slept around on him. I am in the same major as two of Greg's good friends, Jake and Melissa, so we have several classes together each quarter. They ignore me when we have group discussions and have left me out of group emails when we've worked together on class projects. When I began dating another person in our major, Melissa "enlightened" him about my true character. Thankfully the guy disregarded her slander, but now I feel like I have to address Jake and Melissa's resentment toward me. I'm not sure what to do, though, probably because I'm pretty frazzled right now. For personal reasons I'd like to keep the stalking quiet, but maybe telling them what really happened is the only way to get them to stop?

A: I think you should discuss this with a dean of student affairs or someone in the counseling services. You don't want to be seen as wilding spreading stories about Greg, but stories are being spread about you and those shouldn't be left unanswered. Discuss with these adults what to do, and even if there are legal issues involved in releasing information about what happened. He was expelled, but his friends think he left over a broken heart—which is quite lame on its face—and are excluding you from class information, so something has to be done. It could be that your friends could use the grapevine to help enlighten everyone about the circumstances of Greg's departure. Stalking is a serious crime and I'm glad to hear your university took action.

Q. Re: Sister's Tape: I doubt the little sister's escapades are on actual tapes—it's probably digitally recorded on a cellphone or computer. The little sister needs to make sure her boyfriend deletes these videos. Even if he is a good guy who won't disseminate the videos online, his gear could be hacked or stolen!