CHINA'S young middle-class couples are torn between two daunting moral and financial obligations: their children and their aging parents - and they cannot afford both.

At 33 years old, Beijing office worker Lin Xiaohong constantly frets about her mother's health. Her heart aches every time she remembers how the 60-year-old, almost blind with cataracts, stumbled when looking for her seat on a train back to her home province, Heilongjiang, in northeast China.

Lin's father died of a cerebral hemorrhage three years ago, a loss her mother describes as "not entirely bad" because his medical bills would have been a heavy burden for Lin and her husband, Zhang Bin.

Lin and Zhang are among China's first generation of only children. Both grew up in Qiqihar, an industrial city in Heilongjiang, and found jobs in Beijing after graduating from university.

Theoretically, they belong to the high-income bracket, with a combined annual income of 160,000 yuan (US$23,530), a Toyota Corolla and a two-bedroom apartment for which they still have to pay about 40,000 yuan a year.

Still, the couple face the dilemma of having to care for their 5-year-old son and aging parents. "It's the real-life version of the paradox of who to save first when your parents and children are in peril at the same time," says Lin.

The couple have about 100,000 yuan in savings, which could all be spent on sending their son to one of the city's best schools next year.

Though public education is free in China from primary to junior high school, dozens of "key schools" charge "sponsorship fees" ranging from 30,000 to 120,000 yuan for most children.

While their two-bedroom apartment is apparently too small for three more people, Beijing's housing prices - at least 30,000 yuan per square meter downtown and 10,000 yuan in suburban counties that is an hour's drive from their home - thwart their plan to buy a separate apartment for their parents.

Lin's mother had a cataract removal operation in 2008. "I spent 10 days with her. Thank goodness my aunt and cousin helped take care of her when I had to get back to work," says Lin.

Her own son, however, has not even an aunt, uncle or cousin. In a few more decades, these words for family relations could disappear from colloquial Chinese.

When her mother's cataracts returned last year, the elderly woman refused another operation. "I know she worries about money," says Lin.

Lin's mother and their in-laws all chipped in by borrowing money from relatives when the young couple bought their apartment in 2004 - and they spent at least a year repaying the debts.

They were all forced to retire early from ailing state firms and had little pension income. Like many Chinese parents, they spent all their savings on their children. It's often too late when they realize that they, too, need money and help in old age.

Most Chinese parents finance all their children's education, job-hunting (which sometimes requires bribes and other sweeteners to build up the much-needed "connections"), weddings, home purchases and even rearing of the grandchildren.

When they become reliant on their children in old age, however, life often becomes tougher on all three generations.

Middle-class crisis

About 167.14 million, or 12.5 percent, of China's 1.3 billion people are aged over 60, according to official statistics released last year.

The younger generation, particularly "new immigrants" to big cities, are feeling the growing burden of the graying society.

The pressure is even higher on Lin's boss, 42-year-old Wang Daguo.

Wang and his wife make 20,000 yuan a month and own two apartments, one of which is leased and brings an extra 3,000 yuan a month - a fund the couple saves for their 14-year-old daughter's college education.

Their parents, all aged over 70, suffer chronic illnesses and have little pension income.

At least three times a year, Wang and his wife travel back to their home provinces of Jilin and Henan. "They have trouble moving around. Even cooking and grocery shopping have become real challenges," says Wang.

Wang wishes his parents and in-laws could all stay with them in Beijing, but again, money and housing are real problems.

"We'd need a third apartment. But housing prices are sky high these days and we'll have to spend more than half of our income to repay a mortgage," he says.

Wang's colleagues think he is joking when he complains of money troubles. "They say I'm middle class," he says. "But the middle class is so fragile these days. If I lose my job one day, it's hard to imagine how my extended family of seven people would survive."

Not to mention sudden illnesses or old age provisions for him and his wife. "No time to think about that," says Wang. "For at least 10 years, we'll have to slave for our daughter and parents."

The Chinese Academy of Social Sciences has listed nearly a quarter of the Chinese population as "middle class," including Wang, Lin and younger fang nu or "house slaves" who make 60,000 a year, but spend half of their income servicing home loans.

The group, considered the mainstay in China's social and economic development, are struggling with soaring prices, growing pressure at work and at home, and sometimes fear of losing their jobs.

Finding a balance between work and family, between young children and aging parents, is often the hardest part.

Most new graduates in Wang's company already dread the future. "Owning a home is already castle in the air - it's hard to imagine how to support their aging parents in 10 to 20 years," he says.

Knowing new homes are unaffordable and the traditional family pattern of "three generations under one roof" is unacceptable, Wang and his wife once visited a senior citizens center in Chaoyang District, east Beijing, about 30 minutes' drive from their home.

They never told their parents about the trip.

"It's true the elderly lodgers are provided for, and cared for properly. They also have peers to spend time with - in this sense it's indeed an ideal place for 'empty nesters'," says Wang.

Senior care

But the lack of family love and the distress over being "deserted" haunt many, since many elderly people expect care and attention just like children. "I met an old lady in her 70s, who cried and grimaced every Friday, demanding she must see a doctor," says Wang.

"Her nurse said she simply feared her children would not visit her the next day and thought a medical problem might prompt them to visit her."

Beijing, a city with 2.6 million elderly people aged over 60 - about 15 percent of its population - has 386 nursing homes that together can accommodate 62,000 people. At least 6,000 places were added this year, as the government responds to the aging society.

These institutions charge 2,200 yuan to almost 10,000 yuan a month. The per capita disposable income for urban Beijingers was 2,400 yuan this year, according to the municipal statistical bureau.

According to the Beijing Committee on Aging, one in every three Beijingers will be over 60 by 2050, when the over-60 population will hit 6.5 million.

"The aging population will be a severe problem in the future," says Qi Shuying, manager of Sijiqing Nursing Home, one of Beijing's oldest and best-known facilities for seniors. "Providing more nursing homes and elderly people's apartments will undoubtedly become a trend.

"About 1,000 people are on the waiting list," says Qi.

In a recent survey of 2,264 senior citizens, the Beijing statistical bureau found more than 30 percent of the respondents were seriously considering moving to a senior citizens center.

Many people, however, feel such a move is like to turn their aging parents out.

"Nursing home for my mom? No way! I'd rather risk losing my job," Beijing government employee He Wei says firmly. But caring for her widowed mother - who suffers hypertension and had a cancerous kidney removed last year - means seeing her husband and 8-year-old daughter only on weekends.

When her husband travels on business, the girl must stay with neighbors.

"I'd certainly have another child if I could," says He. "A sibling would give my daughter a helping hand from time to time."