Victim Dharmendra was thrashed to death on Sunday night by his mother-in-law's live-in partner Rajendra, Senior Superintendent of Police (SSP) Rakesh Singh said.
On not getting any food, the boy on Sunday went to their neighbour's house where he had food, which infuriated the accused.
Rajendra started beating the boy, after which he made him sleep. The minor was found dead in the morning, with the accused absconding from the scene, the SSP said.
She went to her native place in Tikamgarh in Madhya Pradesh on Saturday leaving her sons behind with the accused, the SSP said.
The body has been sent for postmortem, police said, adding that an FIR has been registered in the matter.
A search is on to nab the accused, they said.