Dorothy Chiado has followed a path that would be familiar to thousands of Pittsburghers and millions of Americans.
She married at 19 after the end of World War II. The "starter home" she and her husband, Don, bought in Wilkins in 1950 became the only house they would ever occupy.
They raised four children there, with just one bathroom and three bedrooms. Mr. Chiado worked at Westinghouse Electric Co. for his entire career, and when it was time for the children to go to college, Mrs. Chiado took a job as a secretary to help pay their way.
Now widowed, Mrs. Chiado gets a generous Westinghouse pension and Social Security that cover much of her $3,600 monthly payments in the assisted living unit at UPMC Seneca Manor in Penn Hills.
Her children have come to maturity in a different world.
By the late 1990s, her youngest son, Eric, and his wife, Kelly Knieling, were living in North Huntingdon, a prototypical middle-class community in Westmoreland County.
Mr. Chiado had a good job as an engineer and they had one child, but somehow, they went over their credit card limit one Christmas and realized they were having trouble staying afloat.
"I think we were just tired of always not having enough money," Ms. Knieling recalled. "Anything we needed was always an emergency. We'd have a car emergency and then to fix it, we'd have a money emergency. We didn't have the cash to buy anything, and everything we had to do we ended up charging because all our money was going to pay the debt."
About the same time, Tom Alberts and Jackie Gorski met while she was on a vacation trip to Albuquerque. Each of them had been earning about $50,000 a year, but both wanted to move into new careers. They moved back to her hometown of North Huntingdon, and got married two years ago.
Today, both families still think of themselves as middle class, but their economic fortunes have headed in different directions.
Mr. Chiado and Ms. Knieling have managed to climb out of debt through a lot of hard work, adhering rigorously to the low-debt lifestyle promoted by Christian financial adviser Dave Ramsey, and steady pay increases that give them a household income of $120,000 a year.
Mr. Alberts and Ms. Gorski together were earning only $32,000 at the start of this year, largely because Mr. Alberts spends most of his time as the caretaker for his wife's mother, Emily Gorski, who was diagnosed with Parkinson's disease in 2001. And then, last month, Ms. Gorski found out that she was being laid off.
Don and Dorothy Chiado are a classic "Greatest Generation" story, but it wasn't just modesty, hard work and company loyalty that made them typical of their generation.
They also benefited from an American economy that was sharply different from the one their children live in.
For the three decades between 1949 and 1979, family incomes in America rose evenly for every fifth of earners, from the bottom 20 percent through the top 20 percent. In other words, a strong economy lifted all boats at about the same rate.
Since then, the rich have pulled away from everyone else. A new study by the nonpartisan Congressional Budget Office showed that between 1979 and 2007, after-tax income for the top fifth of earners went up by 103 percent, compared with 40 percent for the middle three-fifths of earners and just 18 percent for the bottom fifth.
The greatest benefits went to those at the very top. Research by economists Emmanuel Saez and Thomas Piketty shows that the top 1 percent of earners increased their share of pre-tax income in America from 8 percent in 1979 to 18 percent in 2008, the highest level that group had garnered since 1928, the year before the Great Depression began.
There is a hotly contested, unresolved debate over what caused the rich to get so much richer over the past three decades, and whether that is a bad thing.
Conservative economists argue that the United States emerged from World War II with a huge advantage over other industrialized economies that were devastated by the conflict, and that America's edge began to diminish naturally after those first three decades.
Libertarian economist Tyler Cowen of George Mason University, in his book "The Great Stagnation," contended this year that America prospered for much of its history by reaping the "low-hanging fruit" of cheap land, technological innovations and low-cost immigrant labor, but said the rate of innovation and the nation's wage advantages have slumped.
On top of that, he said, much of the new wealth in America has been going to people on Wall Street -- a fact that has earned the enmity of both the Tea Party and the Occupy Wall Street movements.
In 2004, Mr. Cowen wrote, "The top 25 hedge fund managers combined earned more than all of the CEOs from the entire S&P 500. The number of Wall Street investors earning over $100 million a year was nine times higher than the public-company executives earning that amount.
"When I look back at the last decade, I think the following: There are some very wealthy people, but a lot of their incomes are from financial innovations that do not translate to gains for the average American citizen."
Liberal economic thinkers point to at least two other long-term trends that may have tilted the playing field in favor of the wealthy.
One is lower tax rates on the rich. The other is declining union membership.
An April study by the Institute for Policy Studies noted that 50 years ago, in 1961, there were 12 income tax brackets for those earning more than $380,000 in today's dollars, ranging from 62 to 91 percent. Today, there is one bracket for that group, with a rate of 35 percent.
In an interview earlier this year at his offices at the University of California at Berkeley, former Clinton administration labor secretary Robert Reich said that the 1950s "was a terribly crass and materialistic and conformist age in many respects."
But it was also a decade, he said, when "it was possible to have a consensus behind the largest infrastructure project in American history -- the interstate highway system -- and the largest investment in education this country has ever made through the expansion of public universities and K-12 systems, and through that entire time we could have a marginal tax rate on the highest earners of over 70 percent and we could expect that the rich would pay a larger portion of taxes, and it was unseemly for chief executives to earn more than 30 percent beyond what average workers would earn."
The intervening years also have seen a sharp drop in unionization, falling from a peak of about 35 percent of American workers in the mid-1950s to 11.9 percent last year, the lowest level it had reached in 70 years.
Jacob Hacker, a political science professor at Yale University, contended the declining influence of unions not only has hurt middle-class wages, but has removed an important lobbying force from national and state politics. He is co-author of the book "Winner-Take-All Politics: How Washington Made the Rich Richer, and Turned Its Back on the Middle Class."
"The Wall Street lobbyists are in Washington every day for the long run," he said in an interview at Yale earlier this year. In the past, he said, "there was a lot more dense organization linking middle-class voters into politics, whether it was unions or civic organizations," and that gave middle-income citizens a greater voice in economic policies.
"If it was within my power," Mr. Hacker said, "I would double the share of workers in unions. I think it would have a huge effect, although I think now, saving them from extinction is the best we can hope for."
Over the past three decades, many middle-class Americans have not realized that their share of the economic pie was diminishing, Mr. Reich said. Their lifestyles were propped up by women entering the workforce, couples sometimes working longer hours and people borrowing against the fast-rising value of their homes.
The collapse of the housing bubble and the resulting recession have exposed those weaknesses for millions of families, he said.
"The frustration is palpable. Because the reversal of the economy starting in the late '70s was masked by these three coping mechanisms of women flooding into paid work and people working longer hours and everyone going deeper into debt, it was still possible for the middle class to believe in the American dream.
"It's only recently that they've said, 'Oh, this was all a fraud.' "
Dorothy Chiado, who is now 83, would not put it that harshly.
"I just shake my head," she said. "Eric and Kelly only have one child. I don't know how some of these families with three or four children manage these days."
Correction/Clarification: (Published November 15, 2011) Dorothy Chiado lives in UPMC Seneca Manor. A story Sunday on the challenges facing the middle class listed an incorrect residence.
Mark Roth: firstname.lastname@example.org or 412-263-1130.