An alleged mentally ill 14-year-old boy was kept locked in a filthy room of a mice-infested trailer for three years by his own mother.

Amanda Joliff, the teenager’s mother, who described her son as “developmentally delayed”, only allowed him out to take care of the family’s ducks, to clean and to eat, according to police.

It is reported that the boy ate only about four times a week.

It also appears that authorities missed numerous chances to intervene despite visiting the address numerous times.

Police visited the trailer at least three times since 2007, but, incredibly, failed to notice that anything was wrong.

Amanda Joliff, her boyfriend Richard Smith and the boy’s sister had kept him locked in the room since early 2008, the teenager told police.

According to police, the boy's room was filled with junk and had a soiled mattress with no sheets

The boy was found on September 27, hiding under a neighbour’s porch, while his mother and her boyfriend took a trip to New York.

According to police, the boy’s room was filled with junk and had a soiled mattress with no sheets. The only window was boarded up and there appeared to be a leak in the ceiling.

It appears that mice had eaten through boxes of pasta which were his main source of sustenance.

Two dogs, six birds including two ducks, and four toads lived inside the trailer, and another dog lived outside.

The home reeked of animal urine and faeces, police said.

The child’s mother, Amanda Joliff claimed that the lock on the plywood door to the boy’s room was originally installed because he had once run away.

Amanda Joliff admitted to locking the boy up when she got upset with him or when he was in trouble, police said.

Amanda Joliff, the teenager’s mother, who described her son as “developmentally delayed”, only allowed him out to take care of the family's ducks

The boy’s father and sister decided to move out of the trailer on September 27 but told him he would have to wait another day to leave, the teenager said.

His father gave him $5 to find a place to stay and he crawled underneath a neighbour’s porch to sleep, too afraid to ask for help, the boy said.

Police acknowledged Friday that they previously had visited the home but had seen no signs of abuse.

Authorities were first called to the address in February 2007 after the family’s dog bit a boy.

A male child who lived at the home showed up at a bar to listen to country western music in August 2010 after which police took him home.

In 2011, police were again called to the home because neighbors had complained about unlicensed dogs.

Lt Lee Mathis said authorities never entered the home during those visits and didn’t notice anything suspicious.

“If we had any indication of what was going on, we would have taken action,” Lt Mathis said.

Amanda Joliff, 36, and her boyfriend Richard Smith, 31, have been jailed on charges of false imprisonment, child abuse and neglect.