"My son just wished me a 'Happy Birthday' on Jan 23. I miss him so much. I was hoping we would spend Spring Festival together, and I would cook delicious food for him. How can I live without him."

The mother of Guo Peipei was overcome with emotion after her son's death. Guo, a 23-year-old student at Harbin Medical University, was an intern at Beijing's China-Japan Friendship Hospital. He was killed in a gas poisoning accident with four schoolmates in their rented apartment on Monday.