Story highlights China's one-child policy has been in place since 1979 to try to curb population growth

But many Chinese are now questioning the policy and skirting the law

Wealthy families pay fines or travel overseas to have a second child

There are increasing official signs that suggest China may relax the policy

Something isn't quite right with this picture. There seem to be too many children here. Isn't this the country famed for its one-child policy? Aren't there big fines and penalties for having that second child?

A man is watching two children play. He says both of them are his.

"Many people here have more than one child. Some have four children," he adds.

This migrant workers' village on the outskirts of Beijing is typical of itinerant communities, where families are finding ways to beat the system.

The one-child policy has been in place since 1979 to try to curb China's population growth. It has worked -- some estimates say hundreds of millions of births have been averted.

And it hasn't been bad for the economy, either. As China has opened up, hundreds of millions of people have been lifted out of poverty as the nation's economy grows faster than the population.

But there have always been loopholes. The wealthier families have paid fines, and some have traveled overseas to have a second child with a foreign passport. China's ethnic populations have been largely exempt as rural families have multiple children to help work the fields. Offspring of one-child families who then marry also may have more than one child.

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In this migrant village, however, one father says he thinks this has always been an unfair policy.

"What has fairness got to do with it?" he says. "If you have more money, then you can have more children; and if you're poor, you only have one child."

He won't reveal his name and doesn't want his face photographed. But he is willing to talk.

He says people here sometimes pay brokers to bribe officials for documentation for additional children. It can cost up to $1,000 but is still much less than the official fine, which can be as high as 200,000 Renminbi, or more than $31,000.

In his case, he waited until his second child was born and registered both together as twins.

It is illegal, and he says people worry about being caught but are willing to take the risk.

The Zhang family decided to have a second child more than 20 years ago.

It certainly wasn't fashionable or patriotic. They paid a big price -- not just a hefty fine, but the father, Zhang Jian, even lost his job.

"Yes, once I had two kids, I lost my job. But I'm not scared of that, I don't care. The most important thing is to raise my kids. This is for happiness," he says.

His daughter Zhang Dongjuan is forever grateful for her parents' sacrifice.

"I am very happy. I'm the luckiest girl in the world," she says.

She shows me photos of her sister, now away from home working as a banker. They are very close, she says.

Dongjuan says her friends were always envious of her, and she's already planning to have two children when she marries.

"Yes, I think the policy should be finished, because we all have a lot of pressure if we have just one child," she says. "If we have two children, then four people can afford to look after two set of parents, we'll have less pressure."

There are growing calls for an end to the policy. Critics say China's population is aging and is heavily weighted toward male children. Eventually, they say this will have a serious impact on the country's economy and social cohesion.

On advertising billboards now there is a new image. One in Beijing promoting Chinese values -- patriotism and inclusiveness -- shows grandparents, parents and, yes, two children.

It is in stark contrast with another more horrifying image. Last month a photo appeared on the Internet and quickly went around the world showing the brutal side of the one-child policy: a mother forced into an abortion lying exhausted and disheveled on her hospital bed, beside her a fully formed fetus.

Between these two images -- the new Chinese poster family and the exhausted mother -- lies the reality of a policy that has defined China for three decades, but is now being questioned.