She said the boy had once hurt himself using a compass and jumped into a river though he did not know how to swim. He was later rescued.
"Before he took the extreme step, my son had deleted the game from his mobile phone", the woman added.
The statements of the family have been recorded and investigations are on, police said.
The Centre has directed internet majors - Google, Facebook, Whatsapp, Instagram, Microsoft and Yahoo - to immediately remove links of the 'dangerous' online game, which has reportedly led to suicide of children in India and other countries.
On August 12, Kerala Chief Minister Pinarayi Vijayan had urged the Centre to take immediate steps to ban the Blue Whale Challenge in the country 'to save precious lives'.