My sister insists on keeping in close touch with my ex.

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Dear Pru,

My dilemma is probably not as unusual as I think it is, but here goes. My younger sister has always seemed to want to maintain a relationship with my ex. (We split up over 10 years ago.) The first few years she said it was because the kids were over there on weekends, but now my children are teenagers and are seldom there … but she goes over anyway. She goes on vacation with him and whoever his latest girlfriend is; she goes over for his birthdays, picnics, whatever, but lies to me about it—and tries to get my children to lie to me! That really makes me angry. First, I do not expect my own sister to lie to me; second, I do not expect my children to lie to me. So … for the last 10 years, we have been having the same argument. I have never heard of someone maintaining more than a casual relationship with the sibling's ex. So I finally told her that if she wanted to continue this, she could write me off. Am I wrong? Should I not expect some kind of loyalty from my sister?

—Thank you,

Annoyed Big Sister

Dear Ann,

You are not wrong. Your sister is either a) hostile or b) sweet on your former husband. It is one thing to maintain a cordial relationship with a relative's ex but quite another to do it your sister's way. P.S.: Your previous husband AND the girlfriend du jour sound kind of wacky to go along with this threesome business. You have Prudie's permission to be done with the situation, your sister, and the whole mess.

—Prudie, decisively

Dear Prudence,

I live in a neighborhood where the houses are pretty close together. I like to sunbathe, and the place with the most privacy for me was my upstairs deck, until my neighbor built a two-story-tall jungle gym for his three young boys right on the property line. Now I don't feel comfortable going out there when they are on it, which is pretty much all afternoon. I am not in the nude, but it doesn't feel right; it also doesn't seem right that I should be cooped up inside. It was bad enough when they were just outside screaming and yelling; now I am under their surveillance. Should I just go about my merry way and let them see their neighbor in her bikini, or should I banish myself for the mental health of the innocents?

—Bathing Beauty in California

Dear Bath,

You are a good soul to consider the corruption of your young neighbors, but Prudie thinks your concerns are unwarranted. With one wrong turn of the TV dial, they could see any number of people without even the bikini. And it is Prudie's understanding of little kids that seeing the neighbor lady in a bikini, no matter how fetching, would come in second to the physical activity of rough-housing and swinging around. At the worst, the sight of you sunning would be like seeing their mother in her underwear. Try to ignore them, and don't forget to use sun block.

—Prudie, nonchalantly

Dear Prudence,

I've been dating a wonderful man for just over three months. I've completely fallen for him, and I think he feels the same way, but we're just taking one day at a time. We've both been burned in previous relationships. The problem is: We both have back problems, but he prefers his waterbed, and I prefer my firm mattress. We love being together, but when I stay at his place, I can't sleep. It's a "wavy" bed, and I wind up rolling into him and am uncomfortable the whole night. Then I wake up with excruciating back pain. When he stays at my place, he doesn't have enough room, and he's not comfortable either. Since it's only been three months, it's not like we can go buy a bed together. Any suggestions?

—Sleepless