She was in her 50s.
A family member of Khan confirmed that Nahid, who had been fighting cancer for long, died at a Canadian hospital yesterday. Her body will be flown back to Pakistan in a couple of days.
Khan, a master of qawwali singing, passed away in 1997 at the age of 48 due to multiple organ failures. After his death, his widow moved to the UK and then to Canada.
The couple had no child.