The death toll in the domestic LPG cylinder explosion at a house in Domalguda last week reached five on Sunday, with the death of the last child, aged four.
Officials said Vihan, who was shifted to a private hospital for better care, succumbed to burn injuries on Sunday.
It was his six-year-old sister Sharanya Sri, who first succumbed on Thursday, followed by his seven-year-old brother Abhinav, mother Dhanalakshmi and grandmother Padma the next day.