UPDATED 05/10/11 12:37 a.m.

GARY, Ind. (CBS/WBBM) — The father and stepmother of a 13-year-old boy whose body was found in a Gary, Ind., trailer park last week have now been charged with the boy’s murder.

Riley Choate, 34, and his wife, Kimberly Choate, are charged with the murder of Christian Choate, 13, whose body was found encased under a slab of concrete last week. CBS 2’s Pamela Jones gets reactions from neighbors of the family.

Previously, Riley Choate had only been charged with removing a body from a death scene and failure to notify authorities of a dead body, but not with homicide or anything directly related to the boy’s death.

Investigators were tipped off to Christian’s death by Christian’s mother, Aimee Estrada, who said her daughter came to her on May 1 with information about the location of Christian’s body.

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The daughter later told investigators that her brother died around April 5, 2009, and that Riley and Kimberly Choate buried Christian behind a home in the 5900 block of West 36th Avenue in Gary on April 8, in the Colfax Mobile Home Park where they had lived before moving to Kentucky, according to a probable cause affidavit filed in Lake County court on Tuesday.

Following an investigation, Lake County, Ind., authorities found out further that Christian had been kept in a dog cage secured with seven locks for more than a year by the time he died. The dog cage was in Riley Choate’s bedroom.

Christian’s cousin told prosecutors Kimberly had been hitting Christian regularly for some years before she started tying him to a bed frame. Then she started putting Christian in the dog cage, which had been given to the family for their dog, the cousin told prosecutors.

The other children in the house would try to sneak food to Christian, but Kimberly would yell at them and advise them: “He needs to be locked up. He’s a dog.”

Riley And Kimberly Choate

Riley and Kimberly Choate are now charged with the murder of Riley's son, Christian, in 2009. (Credit: Lake County, Ind., Sheriff's Office)

Christian’s sister told prosecutors she was the only one responsible for looking after Christian, including feeding him, taking him to the bathroom, forcing him to do exercises, and physically punishing. She said if she failed to perform these duties, Riley Choate would beat her.

The sister, identified in published reports as Christina Choate, said she believes Christian was kept cage to make sure the boy didn’t tell his biological mother that he was being physically abused. Christian often ran off and tried to make contact with his mother, prosecutors said.

Christian’s sister was ordered to chain the boy to a bed frame on the ground, so she chained Christian’s hands and feet, and hit and him and choked him until he turned blue while recording a video of her actions at Kimberly Choate’s direction, prosecutors said.

The cousin also said she saw Christian’s sister beating him and videotaping the act at Kimberly’s order, and the other children had to watch because they were forbidden from leaving the room.

On April 4, 2009, Christian refused to eat. Prosecutors said Riley got angry and punched him several times in the head before throwing him back in the cage. He then ordered his daughter to check on Christian every five minutes, or he would beat her too, prosecutors said.

The girl followed orders, and on April 5, she checked on Christian as instructed and tried to feed him some cocoa wheats – slapping him when he refused. Soon, she noticed Christian wasn’t breathing, and they opened the cage and attempted CPR with an air pump.

But she later discovered Christian was dead.

The girl said she saw Riley and Kimberly Choate wrap Christian’s body in a two plastic garbage bags and load it into a plastic tote, then haul it off in their van along with several other totes, prosecutors said. Other witness accounts said the girl was ordered to help wrap Christian’s body and duct tape the bags.

Riley Choate allegedly said to his daughter, “If you say anything, I swear to God, I’ll kill you and I’ll bury you with your brother.”

Riley and Kimberly Choate first drove the body to Christina and Christian’s grandmother’s home down the block in the trailer park, and dropped the body off there, prosecutors alleged.

Three days later, the girl saw her father and stepmother covered in mud, and Kimberly Choate said Christian was buried behind the woods behind the grandmother’s home and was “covered in concrete so he couldn’t get out.” The couple had tried to bury him under a shed, but the floor was too hard to break out, prosecutors said.

Christina Choate told the Northwest Indiana Times that her father wrapped her brother’s body in plastic, drove his body across the street and buried him under lime, dirt and concrete. She says she hopes her father is never free again.

Riley Choate admitted that he received a call from his daughter saying Christian was dead, and found the boy lying on his back on a baby mattress in the girl’s bedroom, prosecutors said.

He told investigators: “If I had to do it over, I’d have just called. But I was freaking out.”

He said he put a Bible and a cross on the deceased Christian’s chest over the bags before burying him, prosecutors said.

Riley Choate had taken custody of Christian and Christina six years ago from Estrada, who had given them up.

An autopsy last week ruled Christian’s death a homicide, but the specific cause of death was not being released until the investigation is completed.

Christina Choate has not been charged with any wrongdoing.

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