Kyron's Biological Mom Writes Touching Letter to Missing Son

PORTLAND, Ore., June 22, 2010— -- The biological mother of the missing 7-year-old Oregon boy wrote an emotional letter to her son in which she pleaded for his safe return and apologized for not protecting him.

Desiree Young, the mother of Kyron Horman, wrote to her son in a letter released to the media, "I miss you every second of every day. I would give my life for yours, I just want you back safe. You must come back to us."

Kyron disappeared the morning of June 4, after he and his stepmother Terri Horman attended a school science fair where Kyron had displayed a project on red tree frogs. His stepmother said she last saw Kyron walking down a hallway toward his classroom.

When Kyron didn't come home on the bus that Friday afternoon, his parents called the school, which in turn called 911, launching what Multnomah County Sheriff's Office Capt. Jason Gates said could be the largest search operation in Oregon history.

Now Young writes that she regrets all the time she spent away from her son. While she did have monthly visitation with her son, it was Terri Horman who had raised Kyron since he was born.

"I am so soooooo sorry that this has happened," wrote Young. "I am sorry that I was not there to protect you. I will never be able to forgive myself for being so many hours away when you needed me the most."

CLICK HERE TO READ THE FULL TEXT OF THE LETTER FROM DESIREE YOUNG TO KYRON HORMAN

"I would give anything to run my fingers through your short hair again. I miss having you to hug anytime I want. Night time is always hard for me. I miss you so much and want you back here so that I can protect you from all of the horrible things in this world," she wrote.

The letter is signed simply "Momma."

While no suspects or persons of interest have been named, Terri Horman took a polygraph test over the weekend, one of the woman's friends told ABC News.

Police have not discussed a polygraph test or its results.

Late last week, the Multnomah County Sheriff's Office held a press conference to dispel rumors that Kyron had been safe and to reiterate the department's search efforts for the boy.

"[Kyron] has not been found yet and the community needs to keep looking for him," said Gates. "Kyron we are still looking for you."

Gates read a statement from Horman's stepmother and father, thanking authorities for their hard work and chronicling their heartbreak after two weeks without word from their young son.

"It has been two weeks since our son Kyron disappeared," said the statement. "For the last 14 days we have not been able to talk to him see him playing around the house or tuck him in bed. Any parents would understand the grief that this causes our family."

"Father's day is Sunday. For the first time in seven years we won't have Kyron around to talk to. It hurts us deeply and our hearts are broken," it said.

Kyron's plight has put an unwelcome spotlight on the family. Late last week, the boy's uncle, Kristian Horman, 32, was taken into custody in Washington state following his conviction earlier in the week on charges of child molestation in the third degree. Officials say he had a sexual relationship with a 16-year-old female relative. He will serve six months in prison.

A three-page flyer released by the sheriff's office is seeking information from anyone who was at the school or had children at the school where Kyron was last seen.

Search for Kyron Horman Expands

In addition to photographs of Kyron, the flyer has several images of his stepmother, Terri Horman, the last person to see the boy.

Questions on the flyers include "Did you see Kyron and if so where" and also asks if they saw his mother or her white Ford truck on that day.

CLICK HERE TO READ THE FLYER USED IN THE SEARCH FOR KYRON

The flyers come on the heels of the construction of 30 large billboards with Kyron's smiling, bespectacled face, the words "Endangered Missing."