Zhu Ling, the victim of an unsolved poisoning case in the 1990s, is seen in pictures when she was young and healthy. She passed away in Beijing on Dec. 22, a month after her 50th birthday. Photo: File Photo

Zhu Ling plays the piano in her childhood. Zhu was born in Beijing in 1973 and was a second-year chemistry student at Tsinghua University in 1994 when she was poisoned with thallium. The poisoning made her incapable of living independently for the rest of her life. Photo: File Photo

Old photo of Zhu Ling. She was also good at swimming, and had earned the title of a second-class swimmer in Beijing. Photo: File Photo

Zhu Ling plays the Guqin at a concert in December 1994, when she had already begun to experience symptoms like stomach pain, joint pain and hair loss due to the poisoning. Photo: File Photo

A family photo of Zhu Ling (second from left). Her elder sister Wu Jin (second from right) died in an accident while hiking in 1989 when she was a student at Peking University. Photo: File Photo

Zhu Ling sits in wheelchair in front of her mother Zhu Mingxin at home in April 2009. Photo: VCG

Zhu Ling’s mother(right) helps to comb her hair, while her father Wu Chengzhi prepares breakfast before a hospital visit in April 2009. Photo: VCG

Zhu Mingxing (first from right) helps Zhu Ling into a taxi to visit the hospital for medical treatment in April 2009. Photo: VCG

Zhu Ling undergoes rehab. Photo: VCG