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Dear Prudence,
My sister and I are best friends. She and her husband have a young teenage daughter and a 9-year-old son. I think my sister is a great mom for the most part, and my niece and nephew do very well in school and have friends, but I've recently learned some things about my nephew and my sister that disturb me. She still gives him baths, and he won't even take one unless she's there to assist him. Also, he has been sleeping in his parents' bed between the two of them. They recently downsized to a queen-size bed, and now my brother-in-law is sleeping in my nephew's bed because there's not enough room for all of them. My nephew uses this baby voice when he talks to my sister, which the rest of my family finds quite annoying, while my sister seems to love it. He is also so possessive of her that she cannot be out past his bedtime without him calling her cell phone and demanding she come home, which she does! I don't have children, but is this normal? I am concerned that because of the kind of relationship he has with his mother, he will have difficulties in his adult relationships with women. Should I say something to my sister, or mind my own business?

—Freaked-Out Aunt

Dear Freaked-Out,
No, it's not normal for a 9-year-old to have replaced his father in his mother's bed. Nor is it good that he calls the shots on how late his mother can be out. The baby-talk is also creepy. The bathing habits themselves are not so disturbing, but they're just part of a larger pattern of a mother who is simultaneously elevating her son to the role of partner and infantilizing him. But without such mothers, psychiatrists would spend their days playing solitaire like the Maytag repairman. In cases where a child is in immediate danger, you have to speak up. But in this case, you're concerned that in 20 years, his girlfriend will be writing to an advice columnist describing her boyfriend's sick relationship with his mother. And since the kids are both doing well in life, your sister will take it as a major affront that childless you is questioning her parenting decisions. Obviously, it would be easiest for you to mind your own business. But she's your sister and your best friend. Would you want her to speak up if she felt you were somehow going off the rails? Without giving the long list of particulars (maybe just mentioning the sleeping situation), I think you should gently talk to your sister about this. Tell her that she is a great mother—her kids prove that—but you've been wondering lately if your nephew doesn't seem a little clingy and overly attached.

—Prudie

Dear Prudence Video: Christmas Overkill

Dear Prudence,
My boyfriend and I have been together for a year and a half, and I have never had any complaints about his hygiene, until recently. Driving home from a dentist visit, we got to talking about brushing habits. He confessed to me that he only brushes when he "thinks about it." When I asked him when the last time he thought about it was, he said two days earlier. Two days?! Now, I'm not exactly neurotic about oral hygiene, but I brush and floss at least once a day, and I always brush before I'm going to see him. Since I've never noticed before if he's had bad breath, and certainly his teeth always look clean, I wonder if it's all in my head that I get grossed out about kissing him now. How can I convince him that he should brush his teeth daily without sounding like an overbearing mother?

—Just Wanting a Clean Kisser

Dear Just Wanting,
Back in the day, the day being the Pleistocene, it was probably desirable for men to have food hanging from their beards and teeth so their women could pick up extra sustenance when they kissed. However, not since the Holocene began has this been a plus in the romance department. A survey by MIT found the toothbrush outranked the car and the computer as inventions people couldn't live without (apparently the interviewers didn't call your boyfriend). You are either really in love or your boyfriend has an unusually self-cleaning mouth, since he apparently brushes his teeth only about three times a week and you haven't noticed anything amiss. But now that you know, I can't imagine how you'll stop wondering if his teeth are getting particularly furry before each smooch. You're right not to want to sound like a mother overseeing his bedtime. So go ahead and address it straight on by saying, "I don't want to sound like your mother, and I'll acknowledge you have good breath, but now that I know you don't brush every day, it's really affected me." Show him this article about the connection between plaque and heart disease, and tell him that brushing daily will be better for his health and your relationship.

—Prudie

Dear Prudence,
I am newly wed to a beautiful, talented woman. She was divorced, and I was a widower. Our love life is incredible. Our blended family is compatible. Our openness is remarkable. However, I do have one area where I feel uncomfortable: the prior men in her life. My wife will talk freely about the men she dated when she was single. In particular, she has remained friends with one former lover. She loved him, but she ended their relationship because she didn't find him physically attractive enough. He was badly hurt when she broke up with him. My uneasiness has increased as my wife continues to reach out to him for help on professional matters he has expertise in. Recently, after she called him about computer troubles, he gave her a new computer, which made me uneasy. My wife was hurt that I had problems with her ongoing contact with this man. She thinks I should realize that he's simply a friend now, and I shouldn't feel jealous. What do you think?

—Troubled by Exes

Dear Troubled,
Your wife is one of those people who keeps in touch with former paramours, while you are not. What to her is normal, innocuous contact, to you is a threat to your relationship. In general, I think it's unwise and undermining when a jealous spouse tries to force an end to such innocent contact. And I believe that to your wife, this man is now nothing more than a dear friend. When she told you she wasn't physically attracted enough to him, she expected that you understood she doesn't feel, and never felt, for him what she feels for you. But in this case, I also think your unease derives from something real: He's not over her. And I think you're right that the gift was inappropriately extravagant. Have another talk with your wife about this and explain that while you're not asking for her to end contact with this friend—and you have to mean that, and let go of your jealousy—you think he still carries a torch for her, and you're concerned that her taking such gifts in the future could be misconstrued.

—Prudie

Dear Prudence,
My long-term boyfriend and I broke up about a year ago. While we were dating, he gave me the password to his e-mail. Since the breakup (which was mutual), he has been very distant. A few months ago, I began signing in to his e-mail account, and found that he is dating a new girl. I know that I need to stop doing this—not only is it a huge invasion of privacy, it's also hard for me to see how happy he is now. How do I tell him to change his password without letting on to the fact that I've been checking the e-mail account? I want the password changed because I don't want to cave in to temptation.

—Snooping

Dear Snooping,
You're right—you shouldn't be doing this, but since you feel too weak to stop, send him an e-mail saying that you recently updated your e-mail account and changed your password, and it made you realize that if he hasn't done so since you were together, he probably would want to change his. Yes, it's a coded message, but if he doesn't crack it and change his password immediately, then be glad you broke up with someone so obtuse.

—Prudie