It's best to steer clear of confrontation in the carpool lane. But it's harder to hide the silent judgment in our eyes.
A few days after my son's birthday, I ran into the parent whose son had been a no-show at the party. Her child loudly reminded her that she failed to bring him because she promised him a different outing. He then said, again audibly emphatic, that they didn't end up going anywhere.
The mom tried to avoid eye contact. I tried to pretend the child had not had this conversation right in front of us. The entire exchange was awkward and seemed so easily avoidable: Had she called or emailed in advance, or even apologized on the spot, I would have understood. Family schedules are hectic and packed, and we've likely all experienced an etiquette fail at some point.
As it is, the entire dance of invitation and response has become trickier. Fewer people bother to respond to invitations at all, while the ease of digital invites has escalated the number of events we are asked to consider.
Earlier this year, British parents sent their son's 5-year-old classmate in Cornwall an invoice and threatened to sue for failing to show up for a birthday party. That's ridiculous, but the frustration with the lack of manners is understandable.
"The rules are still the same," said Melenie Broyles of Etiquette Saint Louis. "It is courteous to respond, so hosts can plan a party," she said. Ideally, potential guests should respond within a day or two of receiving an invitation.
"People do not RSVP like they used to," she said. "People wait until the last minute to respond. We don't even consider the consequences of responding last-minute or not at all."
She estimates the rate of response to formal invites to be less than 50 percent until hosts start calling to follow up. Email services such as Evite have a greater response rate because they allow the host to send reminders, and indicate whether the recipient has viewed the invitation. Plus, it takes only the click of a button to hit "yes," "no" or the unhelpful "maybe."
"Being a no-show is unacceptable," writes Emily Post. Chronically failing to respond or show up can derail friendships and alienate relatives.
But the constant stream of invitations can also be difficult to manage. The Facebook invite has elevated the casual get-together or play date into an Event. Then there are public events to which a person's entire "friend" list is invited, which do not require the same diligence in response.
I've received text invites to parties traditionally requiring gifts, along with the steady stream of invites to events in which the hostess is selling a product. Those do not merit priority in response.
But the guideline to check a calendar within a day and respond in some manner is a good habit to instill in our children.
If the RSVP is dying, we should attempt to revive it.
"I think many families are just trying to survive," Broyles said. "But once you realize (you've missed an event or failed to respond), an apology is always appropriate. People appreciate that you acknowledge it."
Oftentimes, it's not until a person has taken on the financial investment of throwing a significant party such as a wedding or similar formal event that they appreciate the importance of a timely response.
A poster on a website for brides-to-be vented about the nightmares of chasing down wedding RSVPs and dealing with odd guest responses, such as writing in a number of guests much greater than the two who were invited.
"I think this is all normal, which sucks, but it's true. I know before I got married, I was a late RSVP'er too. I think you don't realize how important it is until it's you," she wrote.
Broyles advises hosts that if someone doesn't respond, they need to follow up and make sure the guest received the invitation.
In the late 1800s and early 1900s, when invitations were often hand-delivered, the prompt of an RSVP on an invitation was considered unseemly.
"Well-bred people do not use R.S.V.P. on dinner invitations. Your guests will have sufficient politeness to reply without having their attention abruptly called to it," notes "Mrs. Rorer's New Cook Book," first published in 1902.
"Whether the invitation is accompanied with the request for a reply or not, all thoughtful people will recognize the propriety," according to Agnes H. Morton's "Etiquette," from 1919.
That was when all replies, whether regrets or acceptances, were expected to be handwritten and delivered. Anything less was considered vulgar.
Nowadays, technology has made responding easier than ever, which should raise our expectations of manners -- not lower the bar even further.