A Shanghai family’s decades-long devotion to a vulnerable neighbour has led to the city’s first legal guardianship case involving people unrelated by blood.Ren, 71, inherited a quiet act of compassion from his parents, caring for his neighbour Xu, 56, for four decades, the Shanghai Law Journal reported.Xu was born with a mental disability. Originally from Xinjiang in northwestern China, he never married, had no children and has no surviving relativesHe moved to eastern China’s Shanghai in the...