I fear my niece will be injured, or worse, by this unpredictable pet.

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Dear Prudence,
My sister is 20 years old, has an 18-month-old daughter, and is a great mother. She doesn't have much money, so she recently moved in with a new roommate. The roommate has a pet pit bull. I met the dog a couple of days ago, and while she is very sweet, she also seems to be pretty nervous. I know I was a new person to this dog, but overall what I saw was potentially a very dangerous situation for my niece. I told my sister that, and she told me that she trusts the dog and thinks she's well-mannered. She said that the dog and her daughter get along well, the dog doesn't mind if the child pokes her, and that the dog lets the child sleep in her dog bed sometimes! Is this one of those situations where I can't tell her what to do, so I should leave it alone? Or should I call child protective services?

—Uneasy

Dear Uneasy,
No wonder the dog is nervous. Suddenly a small human is sticking fingers in her eyes and sleeping in her bed. You're probably sweet and well-mannered yourself, but surely you would lash out at someone who invaded your home and poked your orifices all day. That a pit bull is involved adds to the potential damage if the dog strikes back, but even a placid basset hound could be provoked to take a hunk out of a toddler's face under these circumstances. When a dog uncharacteristically attacks a child, often the aggressor was the child who simply didn't understand that you can't pull on a real dog's tail the way you can your favorite stuffed animal. Your sister is a 20-year-old single mother; that alone indicates she still lacks the ability to understand how acting on her impulses can lead to life-changing events. You must intervene, but try to exhaust all your possibilities before you consider calling the authorities. Tell your sister that her daughter's safety is at issue here and that even the best-behaved dog can lash out at a toddler. Show your sister and her roommate this article about mixing kids and pets, the point of it being that both girl and dog need to be chaperoned as carefully as if this were a Victorian courtship. Your sister and her roommate must understand that unless their darlings are under direct supervision, they must be physically separated. Add, for the roommate's benefit, that if her dog bit your niece, no matter what the circumstances, it could end up being destroyed. If things don't change immediately, offer to help your sister find another living situation. Explain to your sister you won't let up, because you couldn't live with yourself if you didn't do everything to prevent a possible tragedy.

—Prudie

Dear Prudence Video: Dating Mr. Wrong

Dear Prudence,
I have been married for four years to my very loving husband. We started dating when we were 18 and 21, and made the somewhat unwise decision of marrying when we were still quite young. Unfortunately, we ran into a lot of problems early on in our marriage, and I carried on an affair with another man for 10 months. I made a terrible mistake and know that I have done irreparable damage to our relationship. Either way, I came clean about it. We went to marriage counseling, moved out of the city where the affair occurred, and made a renewed commitment to each other. I couldn't be happier. The problem, however, is that a year later my husband is still punishing me psychologically for what I did. When we get into fights, he likes to say, "Well, why don't you just go back with him then?" He knows this hurts me very much. I have been understanding and supportive in his effort to deal with his feelings on the matter, but I'm starting to think that we might not ever get over it. Is my punishment for this affair that I have to let him verbally abuse me for the rest of my life? I don't know what else I can do to help him and feel that I have done all I can. Help!

—Despondent

Dear Despondent,
You "unwisely" decided to marry, you have done "irreparable damage" to your relationship, and you're "despondent" over the prospect of being "psychologically punished" for the rest of your life, yet you say you "couldn't be happier" in your marriage. You don't sound that happy. Many people meet their spouses as teenagers and go on to have long, fulfilling marriages. Others start chafing at the realization that this first serious relationship is also supposed to be the last—you didn't just have a fling, after all, but a fairly long affair. Of course, it's possible for two people with as rocky a start as yours to conclude that they really do want to be together and make it work. But it never will if one partner is enjoying the view from the moral high ground because it allows him to better aim his verbal dirt balls at the other. You should tell your husband that you need new rules of engagement when you two fight. You have acknowledged and apologized for your violation, so now it's time for your marriage to be about the two of you, not the affair. Tell him part of your recommitment to each other needs to be that the past be allowed to fade away. If he can't agree to that, then you two need to get back into counseling and figure out whether you really want to get old together or whether you want to get out while you're still young.

—Prudie