A dispute between family members resulted in the death of a 30-year-old man at Mangadu here on Monday. Police said S. Gnanavel, a lorry driver, used to quarrel with his wife Koteswari. On Sunday, the couple went to the house of Koteswari's sister, where her brothers assaulted Gnanavel, who was drunk. He was brought to the Government General Hospital on Monday where he was declared dead at 4.30 p.m.