DEAR MISS MANNERS: I would like your opinion on the proper etiquette for when a car stops to allow a pedestrian to cross the street. I believe the polite thing to do is to give the motorist some signal of gratitude and walk quickly across the street. Some feel no need to rush.

GENTLE READER: In the ancient world -- by which Miss Manners means the days before Same-Day Shipping -- there was an understanding that most accounts did not need to be settled on a daily basis.

Dinner guests issued reciprocal invitations at a later date rather than paying for dinner with a present, food or even cash. Friends repaid favors as opportunities arose.

In the case you mention, your haste is understandable, since you are unlikely to encounter this motorist again. But this does not modify the rules. Acknowledge the kindness with a gesture, as you suggest. While there is no necessity to speed up your crossing, there is also no prohibition. There is, however, a prohibition against reciprocating with a rudeness -- stopping mid-street, for example, to check your emails.

DEAR MISS MANNERS: My 8-year-old daughter, Lily, was invited to an informal family gathering at her cousin Edna’s paternal grandfather’s home. Lily is Edna’s cousin on her mother’s side (my sister-in-law), and this was a gathering of cousins on Edna’s father’s side.

But since both sides of this family are quite large, we have never made a distinction in such gatherings. For example, we host an Easter egg hunt where both sides are invited, though we have no relation to her father’s nieces and nephews.

At the recent event, when lining up roughly 20 cousins for informal snapshots, one of Edna’s aunts physically pulled Lily out of the group and said the photos were “only for the cousins.”

I was speechless, but later thought I should have spoken up, saying, “Well, Lily is EDNA’s cousin.” It made my daughter feel extremely unwelcome and I doubt we will accept another invitation from this family. How could I have better handled the situation?

GENTLE READER: Edna’s aunt could have handled the situation better by allowing for different family groupings, none more or less important. The cousins on one side. The cousins on the other side. The parents. The relatives wearing red, yellow and blue.

Absent that, Miss Manners would have suggested you invent your own groupings while extricating your daughter both from the situation and the photograph: “This one is the paternal kids, sweetie. I suppose we’re going to do the maternal side next.”

DEAR MISS MANNERS: Several friends and I have had an ongoing discussion about what to do with silverware placed on the table, but not used during the course of the meal. Does it go into the dishwasher or back in the drawer? Is some rule of etiquette or personal preference the deciding factor? Please provide the tie-breaker answer.

GENTLE READER: It goes back into the kitchen, where a panel from the Health Department inspects it and decides whether or not it is sterile enough for human use. So your curious friends will never know where it goes from there. Sorry.

(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: Does the general opprobrium against women wearing white to someone else’s wedding also apply if it is a wedding between two men?

I have a white cocktail dress with a significant amount of black detailing along its sides. It would never be confused for a wedding dress, but I have refrained from wearing it to weddings and rehearsal dinners to avoid any risk of offense. As a result, it doesn’t leave my closet very often.

I am attending a wedding between two men. I am absolutely certain neither will be in a dress. May I wear mine?

GENTLE READER: Might there be an additional reason that you should not wear this dress to that wedding? Is it possible that the attending staff, and perhaps even uninformed guests, might mistake you for the bride?

Miss Manners supposes not. But if the bridal couple favors the tradition that deems both white and black unsuitable in a guest’s dress, that would be a good reason. She will refrain from asking why you bought a dress that you have no occasion to wear.

DEAR MISS MANNERS: I was at a public dance event. My friend had mentioned that a particular dancer was very good, and that she, like me, was widowed. I later saw an opportunity to ask said dancer to dance, and she politely declined.

Afterward, my friend’s boyfriend chastised me for asking the widow to dance because “her husband died only three months ago.”

Is it inappropriate, at a public dance, to ask someone to dance who is known to be widowed?

GENTLE READER: Why does that unauthorized etiquetteer think that it is up to you, and not to the widow herself, to set the terms of her mourning?

It would be indelicate to invite a newly bereaved lady to attend a dance. But Miss Manners notes that this lady has already decided to go, and to dance. Therefore, that is not an issue. She is free to decline your request, as she did, but not to take it as an etiquette violation.

DEAR MISS MANNERS: My son works at the local ice cream shop. When I dropped him off recently, I asked him to bring me something home. When he got home, he had ice cream with him but didn’t have any for me. He proceeded to sit down and eat it in front of me.

When I asked him the next day why he didn’t offer to share, he said it was because he knew I was on a diet. My daughter then proceeded to tell me it’s OK to eat in front of others without offering to share, to get something else or to just plain wait.

Am I not right? Should people be allowed to eat in front of others?

GENTLE READER: It would appear that you have two children who are innocent of manners. Miss Manners will not inquire why this is the case. But at least let her relieve you of your apparent doubt about whether you should accept etiquette advice from them.

(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: Is it appropriate to say ”Nice to meet you” when you meet somebody for the first time?

I am French, and in France, a lot of people say “enchante,” but it is not polite. And most of all, a woman cannot be “enchantee” to meet a man, because in the “enchante” term, there is an inside meaning of, ”I feel some pleasure to meet you” -- which is not appropriate. We have to say, “bonjour, monsieur; bonjour, madame” and that’s all. The Brits say, ”How do you do?”

What is the best way to salute somebody in the USA?

GENTLE READER: “How do you do?”

But like your enchanted countrymen, most Americans believe that “Nice to meet you” is a polite thing to say upon meeting someone for the first time. Traditionalists sniff that one has no way of knowing at first sight whether it will turn out to be pleasurable to meet a particular stranger. Miss Manners agrees, although she does not sniff at good intentions -- and could point out that “How do you do?” (not being a real question) could also be attacked as illogical.

DEAR MISS MANNERS: When my sister died unexpectedly, my husband’s workplace sent a beautiful plant with condolences to our home. Then my mom passed away three weeks after my sister. Image my (unhappy) surprise when I opened my door to find the florist delivery person with a bunch of Mylar balloons and streamers!

I asked who they were for, and from whom, and was told they were for me, from my husband’s work. Needless to say, I refused them.

I told my husband that I think he should say something to the big boss about how inappropriate it was to send balloons. Everybody chips in for these occasions, and the same person is in charge of ordering flowers/plants.

He refuses to say anything because he doesn’t want to “upset” her. This is really tearing us apart. I want to save anyone else from the indignity of receiving Mylar balloons when their mom dies.

GENTLE READER: Although Miss Manners sympathizes with your dismay, she is aware that the infantilization of society has made it commonplace to mark the tragedy of death with childish things, even when the death was not a child’s. They might even have sent you a teddy bear.

In refusing the delivery, you have already made a harsh statement that may cause your husband’s boss and colleagues to question their well-meant, but thoughtless, gesture. Anything more at this time would be churlish.

However, should there be another bereavement at this workplace, your husband could say that flowers are more comforting than balloons.

DEAR MISS MANNERS: If you extend an invitation to a couple and they decline, are they obligated to send a gift or acknowledge your invitation?

GENTLE READER: An invitation is neither a subpoena nor a bill. So no, this couple does not have to send a present. A reply is, however, obligatory. Miss Manners notes that they did give one, as they have declined.

(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.)