Zhu Xiyong/China Daily

On July 27, 2013, Yuan Xiangzhen suddenly collapsed and was again rushed to the hospital and Peng had to take out a new loan.

"I often cry when I'm not with my son, but I'm really strong when I'm with him. How can you not feel tired when you carry such heavy parcels every day? But the only thing I can do is work harder whenever I think about the debt we owe. One day when I can't work anymore, what will he do? He's got a lot of pressure on him," Yuan says.

Peng receives phone calls every day demanding he repay the money, but he begs for more time.

"During some special seasons, such as those around the online shopping sprees on Nov 11 and Dec 12, we can earn more than 10,000 yuan for the month. However, in the off-season, we can only earn about 7,000 to 8,000 yuan, which means we are far away from repaying the debts," Yuan explains.

In order to save as much money as possible, Yuan rarely has lunch. Most days, she makes do with a steamed bun and a bottle of water. When there is some time to rest, she takes a nap by the roadside, which she says is the most comfortable time of her day, especially when she is sitting in the sun.

The Chinese New Year holiday was not a festive time for them, as their creditor paid them visits pressuring them to pay back the money.

"I only have one goal when I wake up every day－to put an end to the debt," Yuan says.

To add to their misery, Peng, who is divorced, has a 6 year-old son, who has been living relatives since he was 2. Peng tries talking to him by phone but his son always makes excuses not to talk to him.