DEAR MISS MANNERS: I realize we lead a technology-filled life, with cellphones, laptops and so forth. However, lately I have received text messages as invitations to baby showers and birthday parties.

I refuse to attend a party given by someone who does not even have the time to send out proper invitations. Am I being old-fashioned, or am I correct to assume there should be etiquette where proper invitations are concerned?

GENTLE READER: The choice you offer implies that the old-fashioned should necessarily give way, a premise with which Miss Manners does not concur. She agrees that to be taken seriously, an invitation should be issued in a dignified manner. And she also recognizes that there are those who will therefore judge her to be old-fashioned.

So how is it that you might also catch her texting? Or overlooking someone's failure to issue proper invitations? Put that down to two other old-fashioned values: appreciating others' convenience, and overlooking their lapses.

DEAR MISS MANNERS: Our mother passed away two years ago, and now our father has started to date. While I am happy he has a companion (he is 60), my brother and sister are not. They are mad at our dad and want nothing to do with her.

Our dad is very hurt by this, and it is causing some major rifts in the family. Dad recently asked my brother and sister to meet his new girlfriend, but they refused and were very rude about it.

I live 1,800 miles away from home, so I hear about what is going on only through phone conversations. It angers me that my brother and sister are treating Dad like he is doing something wrong.

Is this something only time can mend? Or is there something I can tell my brother and sister to stop their making this a big deal, and letting Dad find some happiness while he still can?

GENTLE READER: Although Miss Manners agrees that your siblings' reactions are selfish, they are nevertheless visceral and unlikely merely to fade. You do have to talk to them, but she cautions against denying that it is a big deal.

To them, it dishonors their mother's memory, or at least indicates that she has been forgotten, which would be a big deal. But as she was also your mother, you may be in a position to persuade them that it does not mean any such thing.

The usual argument is that the deceased would have wanted the surviving spouse to be happy and to be taken care of. The first part is not always plausible in regard to finding happiness with someone else, but the second probably is.

You can make that vivid by saying that your father is growing older (everyone is, so this is true no matter what his age and health), and that you cannot expect them to be always around to check on him. And that while you worry about him, living 1,800 miles away you cannot do so. They may then see the advantage of delegating the daily monitoring to someone who, although by no means a replacement for your mother, is also emotionally attached to him.

(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: My fiance just got an invitation in only his name to the wedding of his childhood friend. This couple is well aware of our relationship status, as they visited our city twice in the past year and stayed in our home.

I think he should just attend the wedding on his own, since my understanding is that an invitation covers only the named individuals, period. But my fiance says that a lot of people probably don't know that "arbitrary rule" (his words, which are making me dread the RSVP process when we send out invitations for our own wedding) -- and that the right thing to do is double-check with the bride and groom to spare them the embarrassment of accidentally excluding me.

Can you please guide us in the correct course of action?

GENTLE READER: The prudent course would be to enlighten your fiance before -- as you fear -- his like-minded friends begin distributing their own invitations to your wedding.

First lesson: Rules that are arbitrary may be nonetheless crucial. Whether we drive on the right or left side of the road is arbitrary, but it is crucial to obey the prevailing rule.

Second lesson: That the hosts, not the guests, do the inviting is not arbitrary. Presumably, they know whom they want and have planned for the number of those who have accepted. Even if they do a bad job of it -- and it is indeed rude to invite only half of an established couple -- they should not simply be overridden.

But of course Miss Manners will help you do just that.

Your fiance should say to his childhood friend that he knows the wedding is small, but wonders whether they intended to have room for you. If the answer focuses on the wedding size, it means no, and your fiance may or may not want to attend alone. However, if it was indeed an oversight, this should clear that up.

DEAR MISS MANNERS: I think it is so ugly to hold up your pinky while drinking tea. Do you consider it good or bad manners?

GENTLE READER: It has been both in its day, as Miss Manners recalls.

When tea was first imported to England from China, it was wildly expensive and kept locked up. It was drunk from Chinese cups, which are very thin and, for reasons best known to the designers, have no handles. Therefore, tea drinkers held the cups with as few fingers as possible to minimize scorching, especially of the pinky, which is apt to have fewer callouses than the others and thus be more sensitive.

Because it was a luxury of the rich, that gesture came to be associated with them, and not in a nice way.

As we now have our own teacups with handles, the once-practical gesture is absurd, and only the association with wealth and, by implication, snobbery, persist.

DEAR MISS MANNERS: My friend, who I dated a couple of times, asked me to be his valentine (I received a card and gifts). I accepted. Now, what should I do?

GENTLE READER: How about reciprocating by sending a valentine? And doing whatever the two of you decide, as long as you promise not to tell Miss Manners.

(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: I've been pleasantly surprised with how strangers have treated me during both of my pregnancies. They open doors, carry groceries, offer well wishes -- this list goes on and on.

The issue is that as soon as I've had the baby and am wrestling with the baby carrier, diaper bag, stroller and everything else that goes along with an infant, people act like I don't exist and they don't see me. I'm often struggling to just get through doors as people whiz by without a second glance.

Although I don't think there is any formal etiquette surrounding this situation, please remind your readers that moms need the most support, assistance and often patience after the baby is born, and they are trying to muddle through errands after they've finally made it out of the house.

I am not under any illusion that strangers owe me anything because I'm struggling with all of my baby gear, but the difference in how I was treated when pregnant and then with an infant has always puzzled me.

GENTLE READER: Why is it that the prospect of a new life seems ever more enchanting then the life itself?

Miss Manners is pleased to hear that you were treated well during your pregnancies -- and if the same people who showed you empathy don't understand what comes next, then she needs to have a talk with them not only about manners, but also about biology.

DEAR MISS MANNERS: I've always thought that if a man asks for my phone number in order to schedule a romantic date, it is polite for me to give it.

Some of my friends argue that I should never give my number to a man with whom I am not already acquainted, given that he might be a suspicious character who could misuse the number to harass me or derive compromising information from my smartphone.

My thinking is that any man, whether I know him or not, could be dangerous and that, rather than withholding my phone number (something I believe to be rude), I should continue communication, but act intelligently with a sharp eye for suspicious behavior.

Perhaps Miss Manners can help us understand if and how safety changes the dynamic of the situation.

GENTLE READER: And if these gentlemen asked for your wallet, would you feel it only polite to give it to them as well?

Miss Manners assures you that there is no etiquette rule that decrees one must give out personal information to anyone who asks.

While it is true that anyone could do anything, regardless of how well you know them, you are not tipping the hand in your favor. Erring on the side of safety -- provided that you decline all reasonable requests politely -- is always correct. So is giving your work number to a gentleman who interests you.

DEAR MISS MANNERS: I have a 10-year-old son who hates to write thank-you notes. How can I desensitize my ears to his complaining?

GENTLE READER: Or you could sensitize him, instead, to the relationship between generosity and gratitude. Miss Manners suggests your offering to explain to his relatives that he finds receiving presents to be too much of a responsibility.

(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.)