Kyron Horman Update: Stepmom of Missing 7-Year-Old Barred from Seeing Kids

PORTLAND, Ore. (CBS/KOIN/AP) A judge has barred Kyron Horman's stepmother from contact with her children and from access to firearms, further isolating her from the investigation into the 7-year-old Portland boy's disappearance.

PICTURES: Kyron Hormon Missing: New Photos

The boy's father, Kaine Horman, filed for divorce Monday from Terri Moulton Horman, citing "irreconcilable differences," and requested a restraining order, which was granted shortly after by a judge in Portland.

Investigators have not named Moulton as a suspect in Kyron's disappearance. They have said she's the last person known to have seen him before he vanished June 4 from his elementary school.

The father's restraining order was requested under terms of Oregon's Family Abuse Prevention Act. That document remained sealed, but such petitions are required to cite instances of abuse, or attempted abuse, "with particularity," including dates, according to a guide compiled for the state's court system.

Kaine Horman and Terri Moulton Horman have a 19-month-old daughter, and she also has a teenage son from a previous marriage.  The couple was married in April 2007.

Although they put up a united front for the first three weeks after the 7-year-old disappeared, that has changed. A statement in support of the investigation was released Monday, but it was only signed by Kaine Horman, the boy's mother Desiree Young, and her husband, Tony Young.

Deputies have asked the public for information on Terri Horman's whereabouts on June 4. She has reportedly taken two polygraph tests.

Anyone with information on the whereabouts of Kyron Horman is asked to call the Multnomah County Sheriff's tip line at 503-261-2847.