Retirement should be a carefree time. After a lifetime's work, those in the autumn of their years have earned the right to take things easy and enjoy life. However, that's not the case for Zhu Ling's parents. If anything, their lives are now harder than ever before.

Zhu Mingxin, 72, and her 73-year-old husband Wu Chengzhi, begin their busy "work schedule" at 7 am every day.

Their shabby apartment, decorated in the style of the last century, has become a mini-clinic; the elderly couple clears sputum from their daughter's lungs, hook her up to an oxygen cylinder and massage her limbs. They've performed these tasks so often that they move like professional medical staff.