DEAR MISS MANNERS: I have a very good friend who invited me and my husband over for dinner and told us to get a baby sitter for our daughter.

I probably would get a baby sitter since my 6-year-old daughter would be bored with the adult conversation. However, I was a bit offended by the suggestion. Am I overreacting?

GENTLE READER? No, because had your friends simply issued the invitation to only you and your husband, you would have understood their intentions without the added insult of instructing you on how to make it happen. Right?

Had everyone stuck with that, all would have been well. Your hosts would have accomplished their goal of having an adults-only evening -- and you would have been spared any offense.

However, Miss Manners cannot help but notice that your reason for potentially procuring a baby sitter was not that your daughter's company was not requested, but that she might have been bored. This implies that you might have considered bringing her, asked or not.

DEAR MISS MANNERS: What is the protocol for sharing mobile phone numbers? When someone gives me their mobile number, I don't assume it's OK to give it out (unless that person has so specified). But people just casually ask for other people's numbers like it's no big deal.

I generally reply something like, "I don't have permission to give it out, but if you'll give me yours, I'll ask him to call you," and often I'm accused of being obstructionist or dramatic. Am I?

GENTLE READER: Not in this case, at least. Miss Manners assures you that yours is a perfectly polite way to handle it. If these people feel that you are being overly dramatic, you might tell them, "I'm sure that you wouldn't want me to give out your number to relentless salespeople or overzealous suitors."

DEAR MISS MANNERS: Is it proper etiquette for parents to be invited to their kids' bachelor/bachelorette party?

GENTLE READER: If such a party were so very proper that parents would not be out of place, Miss Manners suggests congratulating the children on their good taste before declining and getting a good night's rest before the more general wedding festivities.

DEAR MISS MANNERS: My father received two letters from people he does not know, written on yellow notebook paper. They were variants on "Can I buy your house? Please contact (phone number)."

Our house is not on the market and we have no plans to sell. How should we respond, especially because these letters seem importunate and rude? One does not walk up to someone and say, "I love your coat. Can I buy it from you?" Nor does one write letters to strangers that say, "Can I make love to you? Please call (phone number)."

GENTLE READER: Perhaps there is such a thing as a "Not for Sale" sign?

While Miss Manners agrees that these letters are annoying, your father need only ignore them. However, he might want to do a little background check and make sure that his house is not being listed without his consent.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: There is an old saying my mother-in-law seems to have embraced wholeheartedly: "If you have nothing nice to say, say nothing at all."

But isn't the saying meant to spare hurt feelings, not cause them? These deafening silences tell me how my mother-in-law truly feels.

The most recent instance came when I redecorated our front porch. My mother-in-law visited and didn't even acknowledge the drastic changes. Instead of saying something like, "I see you have redecorated the front porch," there was this silence on her end, which told me she didn't care for it at all. On the way out of the house, she stood on our front porch and said she liked the neighbor's lawn.

My mother-in-law believes she has impeccable manners. Those manners feel more like weapons. Am I being too sensitive, and is she correct in not even acknowledging things she dislikes?

GENTLE READER: You have not left your mother-in-law any options. You consider her silence rude. Telling you she disapproves of your taste would be ruder. And Miss Manners finds it hard to believe that the flat statement you propose -- merely acknowledging the change -- would be satisfactory.

That leaves vocal approval, a choice your mother-in-law may find distasteful, particularly if she has reason to fear it will be met with accusations of insincerity.

So her policy is a sound one. Miss Manners suggests that you stop worrying about whether your mother-in-law approves of your front porch.

DEAR MISS MANNERS: I wanted to invite family and friends to our 25th anniversary dinner party, but I can't afford to pay for everyone's meal. Is there a tactful way to let them know they'll need to pay for their own meals?

GENTLE READER: "We want to honor ourselves with a party that we clearly can't afford, so we are inviting you to pay for it. We will pretend to be your hosts, but if you want anything to eat and drink, you are on your own."

DEAR MISS MANNERS: My friend often omits any type of salutation or greeting in her emails. No "Dear So-and-So," or "Hi, So-and-So," although on occasion, she will say "Hi" without using my name and then start her email.

She always signs it with her name -- twice actually, since she has an automatic signature built into her email program.

I interpret this as a lack of respect, and it annoys me so much that I would like to say something to her. But it would probably sound petty to say, "How come you don't call me anything, but sign your own name TWICE?!"

GENTLE READER: Informal emails do not properly require either a salutation or a valediction, although if one uses the former, it is reasonable to pair it with the latter. And if one uses an automatic signature, a valediction is redundant.

Yet Miss Manners agrees that you would look petty to let on that you are keeping score. And if you do, your friend will no doubt counter that she should get credit for having used your name in your email address.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: In a restaurant where there is a sign that states "No shirt, no shoes, no service," why are people allowed in to eat wearing sandals or flip-flops? You know, the flip-flops that we used to wear when we went to the swimming pool.

I see people all the time wearing flip-flops in restaurants. I thought the sign meant if you do not have shoes on, you will not get served. But I see now that most restaurants do not have that sign up like they used to.

GENTLE READER: Do you have any idea what it is like to establish any sort of dress code nowadays?

Employers direct their workers to dress professionally, in terms of whatever the particular profession happens to be. Hosts beg their guests to dress up for their important occasions. Schools issue rules banning vulgar and bigoted outfits. Businesses try to establish a tone they expect their customers to follow.

And what does it get them? Code violators who consider themselves to be fighting -- sometimes with lawsuits -- for the noble cause of freedom of expression.

It appears that only clubs with rough bouncers are able to inspire people to dress symbolically for the activity in which they are engaged.

So Miss Manners doesn't wonder that those who write such codes back away from battles over strict enforcement, especially over such hair-splitting questions as what constitutes a shoe. Perhaps if they notice they are losing customers who want a more dignified -- or less smelly -- atmosphere, they will act.

Or they could just hire a toughie to stand at the door, pronouncing people "tacky" and turning them away. Then the lines will form around the block.

DEAR MISS MANNERS: My sister sent me a text saying she needed to know who from my family would be attending her daughter's wedding. It was five weeks from the wedding.

It said she needed to know ASAP, as it was a small wedding, and good friends could not be invited because of family. She didn't see a reservation for my daughter and son-in-law because the block of rooms at the hotel was full. (They have reservations at a nearby hotel.)

I was very hurt, but she claims I withheld information from her and I am too sensitive. Am I wrong to feel as I do?

GENTLE READER: Yes. And it strikes Miss Manners that for someone with tender feelings about herself, you are amazingly insensitive to your sister's needs.

The lady is planning a wedding. She needs to know who is attending. She went so far as to check the hotel reservations searching for an answer about your family.

But although they decided to go, and took care to notify a hotel, they did not have the courtesy to answer the invitation.

At most, you could wish that your sister had confronted the rude guests, rather than going through you, possibly out of delicacy (or possibly because she didn't have their texting address). But your indignation should be directed at your daughter and son-in-law for embarrassing the family.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)