Mother of missing Oregon boy says she believes stepmother 'planned' his disappearance

The birth mother of an Oregon boy missing for over a month said she believes the boy's stepmother planned his disappearance just as the boy was asking to move out of the stepmother's home.

In a Tuesday interview with NBC's "Today" show, the birth mother, Desiree Young, reiterated her accusation that Kyron Horman's stepmother was involved in his June 4 disappearance.

"Without a doubt, I think it was very planned," Young said.

Terri Horman, Kyron's stepmother, has not been named as a suspect in the disappearance of 7-year-old Kyron Horman. Before he disappeared, Kyron lived with his stepmother and his birth father in Portland. Desiree Young lives in Medford.

"I absolutely believe that Terri Horman is responsible for Kyron's disappearance," said Tony Young, Desiree's husband and a detective with the Medford Police Department.

Terri Horman's attorney, Portland defense lawyer Stephen Houze, did not immediately return calls seeking comment on Wednesday.

Terri Horman has become isolated from the family since Kyron's father, Kaine Horman, filed for divorce and requested a restraining order against her, claiming that he believes she was involved with Kyron's disappearance.

Kaine Horman also said in his request for a restraining order that investigators told him that he had been the target of a murder plot by his wife in late 2009.

On Tuesday, a judge consolidated the restraining order and divorce into one case.

Young has said Terri Horman was supposed to drive Kyron to Eugene on the day he disappeared to turn him over to her and Tony Young to spend the weekend in Medford.

On Tuesday, Young told "Today" she had to work the day of the science fair, and is wracked by guilt that she wasn't there.

"To know that I was four and a half hours away when he needed me to protect him," Desiree Young said, "the fact that I had to work that day instead of going to the science fair like I wanted to, that I feel guilty for, too."

She said Kyron was unhappy in his father and stepmother's house, and resisted being returned there.

"Kyron became increasingly unhappy about not spending time with me," Young said. "He wanted to come and live with us. Several times he would just break down and just sob because he wanted to stay."