Sunita, 31, and her one-and-a-half-year-old son, Karan, were found lying in a pool of blood by a neighbour in the slum area of West Delhi's Jahangirpuri.
Police said the incident took place on Monday night when all the family members were sleeping after a fight between Sunita and her husband, Prakash, 36.
"The accused, Prakash, works as painter and is a habitual drinker," an officer said.
"On Monday, when everybody was sleeping, Prakash, reportedly under the influence of alcohol, took out a brick and a knife and hit and stabbed Sunita multiple times.
"When Karan, who was sleeping with Sunita, started crying, Prakash stabbed him too and fled," the officer said.
A case of murder has been registered against Prakash and a hunt is on.
Rajkumar, a neighbour, said: "Prakash and Sunita got married some 12 years ago. He often fought with Sunita over petty issues whenever she asked him to stop consuming liquor."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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