Liu Ping (32) and his wife Li Zhifang (30) live in the village of Ding Jia Wa, 50 km south west of Beijing. Above the gate leading into their courtyard is the Chinese character for "happiness". It is placed upside-down, so that the character also represents "to come", and passers-by know it means "let happiness come".
Li Zhifang invited me into the yard, where 15 hens and four ducks pecked at the ground under a wooden archway draped with pumpkins, keeping clear of a mongrel dog tied to a persimmon tree. One wall was decorated with a tiled mosaic of birds in flight. The other three sides of the courtyard were taken up with a bungalow, a kitchen house and a storage shed.
By peasant standards they are well off. Liu drives a little "breadloaf" taxi in Beijing and makes 2,000 yuan a month. Li earns another 300 yuan in a factory for packaging carpets, giving them a total monthly income worth £200. They also have a big vegetable plot. But the couple are the envy of their neighbours for another reason. In a country where it is official policy to limit a family to one child, they have two children, and they had them at a younger age than is normally allowed.
"Happiness comes from having a boy and a girl," said Li Zhifang, pouring tea in the family room for her visitor and for her father-inlaw, Liu Zhiching (78), a wiry, bald man with twinkling eyes, wearing only pyjama bottoms and sandals in the summer heat.
The boy, Hongjun (the name means "red army"), is 10 and his sister Hongdan is six. They sprawled on an imitation-leather couch, listening with interest as their mother explained how they got off so lightly for exceeding the quota of one child per family.
"I'm the last in the village to have two children," she said. "At the time, restrictions were not so tight as now. We only had to pay a fine of 1,500 yuan for our daughter. Also the marriage age was not limited then as it is now. These days the man must be 23 before he gets permission to marry." Her husband was 21 on his wedding day.
The father-in-law, a veteran communist who had five children in the days before the one-child policy, interjected to say that a couple now has to wait three years after their betrothal before conceiving. "When a man registers his marriage he must pay several hundred yuan as a deposit," said Liu Zhiching. "If he has a child in the first two years the cash will be confiscated. Only if he has a child in the third year will the money be refunded."
The penalties are also now more severe. The fine for having a second baby has been increased to 3,000 yuan, and the annual tuition fees in middle school, normally 1,000 yuan for the first child, are 2,000 for the second.
"If a couple has two children it is impossible to be chosen as a model family," added the father-in-law. A model family exemplifies the five virtues: being kind to relatives, good to neighbours, hard workers, patriotic - and having one child.
"If they have a third child," he went on, lighting a cigarette and contemplating the unthinkable, "then their residence permit can be cancelled and the private plot of the father confiscated. They will have to register as living with the wife's mother."
No one locally has invited that fate. A women's committee imposes official family planning policy in Ding Jia Wa, which has 2,000 residents, and apparently does its job well. No mother is expecting a second child this year. Punishment applied by such committees can mean social isolation.
Li Zhiafang, an attractive woman with a brown face and a warm smile, explained candidly that "if a wife gets pregnant after having one child, the family planning workers will visit and persuade her to perform an induced abortion".
So can any people have two children without penalty? Of course, they smiled. There are deviations from the rules. For example, if there are two daughters in a family and no sons, they will be allowed to have two children to keep up a strong family line. And if the first child is disabled, a couple is allowed a second child. That happened to a nephew of Li Zhifang.
Later a family planning expert told me of other exceptions to the one-child policy, introduced to check a population growing at the rate of 13 million a year and now almost 1.2 billion.
If both couples are single children themselves (as will increasingly be the case) they can have a second child. So too can a couple with one child from a previous marriage, and a parent with a dangerous job such as shipping or mining, or a farmer who needs labour but whose first child is a girl.
Millions of couples are also getting around the rules in provincial cities, where the market economy has eroded social control and a man and wife can afford the fines (or bribes) to register an unsanctioned birth and pay school fees for a second or third child, and where some officials even welcome the supplement to the local budget.
But not all Chinese families are looking for exemptions. Indeed many newly-weds strongly agree with the one-child policy, and a new generation of urban Chinese is opting out of parenthood as they enjoy China's consumer boom.
"There's a whole lot of people like me, said business consultant, Zhang Ligang (29), as we discussed the problem over lunch at a Beijing restaurant, in between calls on his mobile telephone. They call us danshen guizu, or `single aristocrat', but you would describe us as `Chinese yuppies'. We are aged 25-35 and have an income of 7,000 or 8,000 yuan a month.
"We want to travel. We want to buy cars and houses. We don't necessarily want children." He added with a laugh: "And nobody forces us to have even one child. That way we balance up the statistics."