A 12-year-old girl has taken a job collecting garbage to support her parents, both of them cancer patients, and her baby brother.

Every afternoon, Xiao Sheng carries 23 heavy containers of waste from every corner of a community in downtown Hefei, capital of Anhui province, to a roadside loading site, where a waiting truck takes the garbage away for treatment.

The containers weigh at least 50 kg each and the job is tiring, even for adults. But the girl, who is barely taller than the containers, has been doing the job for more than a year.

She is paid 800 yuan ($128) a month. The wages are expected to cover all the basic needs for her family of four, including her father, stepmother and a half brother who is only 1 year old.

Xiao Sheng's 56-year-old father was diagnosed with lung cancer in 2011, when she was in the fifth grade. She readily took over her father's job, spending two hours carrying garbage after school before rushing home to help her stepmother with household chores.

But toward the end of last year, her stepmother was diagnosed with anal cancer.

Xiao Sheng took up all the housework from that point on. When she was first learning to cook, her hands were burned by the hot oil. "Dad was so sad that he managed to get out of bed and did the cooking with my help," she said.

Knowing they cannot afford high medical costs, her parents have rarely been able to seek medical attention. When her stepmother was in critical condition last month, residents in their community donated 10,000 yuan to cover her emergency treatment.

The family comes from a rural area of Hefei and is therefore not covered by urban social welfare programs. Community officials have offered to buy medical insurance policies for her parents, but were told to wait for another year.

Xiao Sheng's meager wage is the family's only income.

"I don't mind having to work hard," she said. "I'm ready to do anything to save my parents' lives."

The family spends only 15 yuan a day on meals. Xiao Sheng and her father often share a bowl of noodles, each insisting that they are not hungry and do not want anything to eat.

The family's plight and the girl's struggle have aroused widespread sympathy on the Web. Xue Manzi, an investor and prolific microblogger with 10 million followers, donated 15,000 yuan to the family on Wednesday.

As of Thursday, Web users had donated more than 100,000 yuan.