The police said that the accused Rakesh Raghuvanshi wanted to help his sister by kidnapping Manthan.
Rakesh's sister, who was married for the past 20 years, was childless due to which there were constant fights between her and her husband.
"He thought that by giving Manthan to her sister, their family problems would be solved and her sister would not have to face the wrath of her husband," police officials said.
Rakesh worked at a scrap shop behind the stall of the boy's grandmother.
He allegedly took the kid to suburban Wadala first and later took a train to Patna.
"We could traced him through his mobile phone," the police official said.
He made several calls to his brother-in-law because of which he was caught in Chhapra.
"We are finding out if Rakesh's sister and brother-in-law were also involved in this kidnapping," police added.
The police said that Manthan is in good condition, since Rakesh took good care of the kid.
The kid was missing since Tuesday last.
Manthan's father is a labourer, while his mother is a sweeper in a Brihanmumbai Municipal Corporation (BMC) school.
