Recently, I found myself with some extra time before a flight at the Detroit Metro Airport. I passed by one of those mini spa boutiques that offer chair massages and overpriced nail services. I paused to look around inside and gauge how indulgent I felt on this mini vacation.

Was I really going to spend twice as much to get a manicure than I would pay at home?

It was a quick mental calculation. Nah, I wouldn't.

While I was having this minor internal debate, I noticed the toes of a woman standing next to me. More specifically, the warm beige-pink color of her pedicure caught my eye.

"I love that color," I said, looking up and realizing I was probably talking to a model. She towered over me, was super-thin and had perfect skin and hair.

"Thanks," she said, adding that it was her favorite shade and she wore it all the time. She started looking through the display of polishes in front of us to see if she could find it for me.

Alas, they didn't stock OPI's Samoan Sand. Before I had a chance to make a note of the color in my phone, this stranger says to me, "You know, I have a bottle in my bag. Just take it."

What.

Did she really just offer me her favorite nail polish? I weakly objected, but I didn't walk away, or stop her from rummaging in her makeup bag. When she couldn't find it in her purse, she opened her carry-on luggage and looked through her clear bag of products.

Eureka. She held it out like a precious gift.

Humbled and a little embarrassed by her generosity, I opened my own cache of traveling essentials.

"Let's make it a trade," I said. "Take this blush. It's my favorite." (For those playing at home: MAC's Warm Soul.)

"Sure," she said. "I'll try it tonight."

We swapped cosmetics and walked out of the airport spa, each in opposite directions. We didn't exchange names or Twitter handles. Maybe we recognized a kindred spirit in one another that travelers sometimes stumble upon.

It reminded me of an incident on a flight 20 years ago.

I was flying from Houston to London, and was seated next to a British man also in his early 20s. We were in the last row and struck up a conversation. He was hilarious in that dry British way, and I was boisterously friendly in that Texas way. We laughed for much of that transatlantic flight, even after they dimmed the lights and the other passengers fell asleep.

He was launching a new product line in an elite hair salon in Los Angeles. I asked for recommendations for my hair, although as a graduate student I was too poor to afford such things. We parted ways, and I marveled at my good luck for having traveled with such an enjoyable seatmate.

A month later, back in the bitter winter of Chicago, a package arrived at my door. It was filled with dozens of hair products and a note from that stranger thanking me for the great conversation.

I probably sent a thank-you note or email, but we never communicated again after that exchange.

For years, I held onto those bottles of hair gel, styling cream and volumizer, probably worth a few hundred dollars. It was a tangible reminder of the kindness of strangers, of meaningful exchanges that might only last minutes or hours, of bonds forged in that limbo space of going from one place to the next.

When I told my children about this latest unexpected airport interaction, my daughter said it sounded like the kind of thing you see happen in movies.

It kind of felt that way, too.

I'll treasure this bottle of polish as much as that hair gel.

Cosmetic products that remind me of what's truly beautiful in life -- who you encounter on the journey.

It's a well-known parental habit to underestimate the trouble your own child gets into.

For some, it's always "other people's kids" who smoke, drink, do drugs or have sex. Turns out, little Johnny and Jane may not be the responsible digital citizens many parents believe them to be, either.

The Center for Cyber Safety and Education, based in Clearwater, Florida, commissioned a study last year that looked at how children in grades four through eight use the internet -- and how their parents perceive them to be using it.

Patrick Craven, director of the center, said the organization hired Shugoll Research to survey 192 students and their parents in four cities: Los Angeles, St. Louis, Baltimore and Bethesda, Maryland. While the sample size is too small to generalize to a national population, the results reveal a sizable disconnect in parents' perception and children's actual use of the internet.

Even in this relatively young subset, nearly half said they had used the internet at 11 p.m. or later on school nights, in ways other than doing homework. A third of the kids surveyed, and nearly half of the middle schoolers, said they had been on at midnight or later. Only 11 percent of parents perceived that their children were online that late at night.

That's just one parental blind spot the survey discovered.

About 3 in 10 students admitted they use the internet in ways their parents would not approve of. For the middle schoolers, this rose to 4 out of 10. What were the forbidden online activities they reported doing? Lying about their age to get onto adult websites, listening to or downloading music with adult content, watching movies or programs meant for adults, searching the internet for adult topics and using a webcam to Facetime with a stranger.

Four out of 10 children in the study said they had connected with a stranger online, and more than half of those kids told the stranger they were older than their real age.

When parents were asked if they thought their children were downloading and listening to music with adult content, 63 percent said yes. Actually, only 31 percent of students said they did this. The same was true for movies with adult content: Twice as many parents thought their children were watching them, compared to what children reported doing.

But when parents were asked if they thought their child had chatted with and tried to meet someone they'd met online, only 2 percent thought so. Fifteen percent of kids admitted they had.

"Parents are kind of missing the point," Craven said. This study wasn't even done with high schoolers, he said: We're talking about elementary and middle school-aged kids.

"The results prompted us to create all new materials for parents on our website," he said. The organization's site, safeandsecureonline.org, features a section for parents and guardians, which includes several suggestions:

-- Create a charging station: a spot where everyone's devices get plugged in at night. "You have to get (devices) out of the room," Craven said. Ninety percent of children said they had a device to access the internet in their room at night. Nearly 4 in 10 students said they had been really tired at school because of late-night internet use; a few arrived tardy or missed school due to it.

-- Consider apps or parental controls offered on family plans by wireless providers that allow parents to turn off the Wi-Fi connection in the house at certain times.

-- Make discussions about internet use an ongoing conversation, not a one-time thing. Nearly all children in the survey acknowledged that their parents or school had taught them about internet safety. But many parents have weak follow-through on rules and oversight.

-- Join the social media sites your children and their friends use. In this age group, the most popular ones were reportedly Instagram, Snapchat and Vine, with moderate numbers of kids also using Facebook, Pinterest, Twitter and Ask.fm. You don't have to be an active social media user, but being familiar with how the sites work and periodically checking in is a good idea. "If they know you are on, it will make an impact," Craven said.

-- Play your child's video games with him or her occasionally. Gaming these days has a social media aspect, and involves conversations with other people -- often strangers. While you may be good about picking games rated for your child's age, the in-game conversations with other players may not be age-appropriate.

There's a thin line between regularly talking about online use and lecturing or nagging. Tweens and teens are masters at tuning out the latter.

If this survey is any indication, these conversations require far better follow-through by parents.

Like many families, we talk about college a lot in our home.

In a recent conversation, my seventh-grader made an offhand remark about how she needed to find a way to earn some money for college. It wasn't the first time I'd heard her say something along those lines.

It hit me that she had internalized my own incessant worry: How would we save enough to send two children, close in age, to great colleges?

The soaring cost of college is the top financial concern for American parents.

In its 2001-2015 Economy and Personal Finance survey, Gallup found that 73 percent of U.S. parents worry about paying for their children's college education. That's a higher percentage than any other subgroup worries about any other common financial concern. The second-highest percentage goes to lower-income Americans, 70 percent of whom worry about paying for medical costs in the event of a serious illness or accident.

The fear of saddling children with years of staggering debt is not confined to lower-income parents: Sixty-one percent of parents making $100,000 or more per year still worry about it. Families who earn "too much" to qualify for need-based aid bear the brunt of massive loans that can mortgage a child's future and eat into parents' retirement hopes.

By some measures, college tuition has increased in cost more than any other good or service in the U.S. economy since 1978, according to a recent NPR report. Student debt has nearly tripled in the past decade to $1.2 trillion, taking a huge toll on young people trying to start their adult lives.

Crippling debt is a loss of freedom. It keeps future generations from entering the middle class, which has long been the engine of America's economy.

The debate between the Democratic presidential candidates over tuition-free vs. debt-free college highlights what a centerpiece issue this has become to the middle class.

Bernie Sanders' overwhelming support from millennials -- exit polls in Iowa and New Hampshire, and entrance polls in Nevada, found more than 80 percent of 18- to 29-year-olds supported Sanders -- shows that he's speaking to their concerns. The Vermont senator has proposed that the federal government cover about two-thirds of the cost for states to eliminate tuition at their public colleges and universities through a new tax on Wall Street financial transactions. States would have to agree to cover the remaining third.

Hillary Clinton's "debt-free" plan would have the federal government send large grants to states, to ensure students can pay tuition without loans. States would be required to increase their allocations, while schools would face new constraints on spending. There's a component for family and student contributions, as well.

Both ideas have faced scrutiny for the associated costs and likelihood of getting state legislatures to comply. Republican candidates have criticized both plans as creating too large a tax burden on corporations.

At a time when we've indoctrinated students about the need for a college degree for future success, we've placed it further out of reach. That feels like a cruel joke.

I've told our children about how I worked throughout college and found two or three jobs each summer to help offset my living expenses. My parents kicked in what they could (not much, considering they had five other children to provide for), and I borrowed the rest. My husband worked his way through college, which he entirely self-funded.

We were part of generations that could do that.

We want our children to have the same sweat-equity investment in their future degrees. But we are aware of how much has changed.

Today's average college student, without support from financial aid and family resources, would need to complete 48 hours of minimum-wage work a week to pay for his or her courses, according to an analysis of credit-hour costs and the minimum wage by analyst Dr. Randy Olson.

That's just tuition -- not textbooks, rent, food and other living expenses.

Those who say that this generation's desire for affordable access to college reflects an entitled mentality could not be more wrong. If you were able to attend college when it was affordable yet want to deny the same opportunities to young people today, you are the entitled one.

Their future is also our future. It's selfish and obtuse to shortchange it.