A two-and-a-half-year-old boy, who went missing from his house on Tuesday, was found dead in the Naodoba area of Madaripur's Jajira upazila on Friday.
The victim was identified as Kutubuddin, son of Ismail of the upazila.
Miraj Hossain, officer-in-charge of Shibchar Police Station, said that Ismail had an old enmity with his sister Nargis, a resident of the Banglabazar area.
On Tuesday, Nargis's 14-year-old daughter Hafsa went to her maternal uncle Ismail’s house and allegedly left with her cousin Kutubuddin. Having failed to track down his sister and her daughter, Ismail lodged a complaint at the Shibchar police station.
The mother-daughter duo was subsequently tracked down by the police and questioned.
A further probe led to the apprehension of the two, police said. And the child's body was subsequently recovered from an under-construction building in Naodoba.
