DEAR MISS MANNERS: Some of my (grown-up) family members will pluck loose hairs off their shoulders and clothes, then drop them onto my carpet, without even trying to hide it!

I don’t say anything, but I wonder if I may ask them to put these loose hairs in the garbage can or compost container. I’m pretty grossed out by their behavior. Your thoughts?

GENTLE READER: First, that you need one of those vacuum cleaners that they make for people with hairy pets. Then -- Miss Manners presumes you would prefer to stop the habit -- you could pick up the offending hair and say absently, “Is this yours?”

DEAR MISS MANNERS: We are empty-nesters who always seem to have a guest stopping by for a night. I love having guests. What I don’t love is stripping and making the beds!

Do I need to provide each guest with a new set of sheets? Is it horribly rude and unsanitary to have two subsequent guests use the same set of sheets? Guests are sometimes cousins, if that makes a difference.

GENTLE READER: Are you asking if being cousins makes your guests less likely to think “Ew!” when they open the bed to used sheets?

Miss Manners doubts that. But being cousins does make a difference in that you are probably on more informal terms with them than you would be with an unrelated, infrequent guest. You can therefore leave a set of fresh sheets in their room the day before they depart and say, “Would you mind changing the bed before you leave?”

DEAR MISS MANNERS: Many people’s cellphones are set to show an image when they call. I have a friend who uses a full-face image of her husband -- who has been dead for over eight years -- as "her" photo when she calls someone.

She is in therapy, but still voices her heavy grief all the time. I realize grief has no proper timetable, and I respect her choice to speak about her husband and how much she misses him. But I find it profoundly jarring to see the face of this long-dead man whenever she calls me.

Is there a reasonable way to let her know the image is disturbing?

GENTLE READER: No.

DEAR MISS MANNERS: My father has passed, and we received many condolence messages, memorial donations, meal deliveries, flowers and assistance in other ways. My mother, sister and I all live in different cities.

My dad, sister and I share a last name, but my mother’s is different. I will be writing the thank-you cards on behalf of the three of us. What is the best way to sign them? My name first? My mother’s? We can’t sign with “the Smith family,” as my mom is not a Smith, so to speak.

GENTLE READER: Generally, there is only one signature to a letter, and others are included by preceding it with something like “Charlotte and Kevin join me in thanking you for ...”

However, Miss Manners will allow you to shorten this by identifying all of you as “the family of the late Horace Smith.”

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: I was wondering if my daughter should have sent thank-you cards to my wife and myself when she graduated from college.

My wife said she should have, but I don’t feel the same way. Could you please let me know?

GENTLE READER: In the normal course of events, children take it for granted that their parents feed, clothe and educate them. In happy families, it sometimes strikes adult children how enormous an undertaking that is.

That may bring on a spontaneous burst of gratitude, beyond the usual affection that children who have felt loved and cared for will presumably have been expressing. This may be prompted by special occasions, such as parental birthdays; typically, however, the full realization of the time, energy, patience and money spent occurs when the children have children of their own.

Miss Manners would not have thought that college graduation would bring this on. Does your wife really want to focus on your shared contributions to your daughter’s education, however much you sacrificed, instead of on your daughter’s achievement? Isn’t this the time to tell her how proud of her you are -- not how indebted to you she is?

That may come later. Miss Manners hopes it will not be merely with a paltry card.

DEAR MISS MANNERS: My husband and I have suffered from several years of infertility, and I am often asked why we don’t have children. As it's none of their business, and for privacy reasons, I typically answer with, “Though it’s a desire, it has not come as easy for us as others.”

Whenever someone inquires further, I would like to know how to politely tell them it's none of their business.

GENTLE READER: In polite language, “None of your business” is translated as “That is a personal matter.”

DEAR MISS MANNERS: I am a case manager at a law firm and frequently must call people at another law firm to discuss cases that we have together. Sometimes the receptionist at the other law firm will ask detailed questions as to what the call is about before transferring me to the person with whom I need to speak.

I don’t mean a simple inquiry as to which case the call is about -- I mean detailed questions. In my view, it’s none of the receptionist’s business what the call is about; if the law firm wanted her to have substantive conversations about cases, she would have a different position than receptionist.

On the possibility that she may be following instructions, I’ve never pushed back, but it does irritate me.

Is there a polite way to convey “It’s none of your business, so please put me through to So-and-So” without actually saying that? Or does business etiquette require that I answer whatever questions the receptionist has before speaking with the person I actually called to talk to?

GENTLE READER: Well, this is not a personal matter. And most likely, the receptionist is not being nosy, but rather following instructions from her employers, as you suggest.

Still, you could say, “She’ll know what it is about.” Miss Manners hopes that works.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: I was raised right and know my forks and honorifics, but it seems some rules may have changed. I find myself frequently unsure whether something is a gift, in which case I’d simply say “thank you,” or if I should offer reimbursement.

To wit: 1. A close friend’s daughter was traveling to a European city in which I’d lived years ago. The daughter texted me and asked if I’d like to have something from there. I said "why, yes," and she brought me the item I requested. Gift or reimburse? Does it matter that the daughter is a college student and was traveling on a scholarship?

2. I’m traveling across the country to visit my daughter for the holidays. Her boyfriend’s family is hosting the main holiday meal. They asked if I’d like to go with them to a (pricey) event the day after. Gift or reimburse?

3. In conversation over lunch at work, I shared that I hadn’t been able to find a particular brand of beer that my husband especially likes. A colleague turned up a few days later with a six-pack he’d found at a specialty grocery. Gift or reimburse? Does it matter that the colleague is subordinate to me, though I am not his supervisor?

In each case, I’ve assumed these items were gifts and have said a hearty "thank you," but I wonder if I’m right.

GENTLE READER: If there is even a remote chance that something was not a present, it is far more gracious to ask and be rebuffed than to have assumed incorrectly.

In each of the cases you cite, there seems to Miss Manners to be room for interpretation. If the traveling daughter had brought you an unsolicited souvenir, it would definitely be a present. But your having dictated what it was makes it questionable.

The boyfriend’s family may have had an extra ticket they were happy to get use out of -- or they may have felt it polite to include you, as you were in from out of town. The exorbitant cost of the ticket makes it worth asking.

And while the colleague one was most likely a gift, any question of subordinance makes it prudent to ask.

In each case, all that need be said is, “That is so kind. May I reimburse you?” Unless someone is actively looking for an insult, it would be a stretch to find this offensive.

If they were indeed presents, the giver could simply say, “Don’t be silly. It was my pleasure.”

DEAR MISS MANNERS: My neighbor needed vanilla extract for a recipe and asked if I had any. I gave her a new bottle of extract, saying, "Replace it when you can."

The bottle of vanilla extract was replaced with imitation extract. I will never use imitation vanilla, EVER. What do I do? Do I say something or just chalk it up to her being rude?

GENTLE READER: “Oblivious” might be more accurate. Miss Manners would rather attribute the mistake to benign ignorance than willful malice.

Some unfortunate people simply do not know the difference between their vanillas. Etiquette dictates that if you feel compelled to educate them, you do so kindly, without accusation, and in another context.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)