BOISE, Idaho - A judge has delayed until next January the federal trial for a man convicted in a brutal attack on a Coeur d'Alene family.

Joseph Edward Duncan III, a Tacoma, Wash., native who previously pleaded guilty in Idaho state court to killing three members of the family in a 2005 attack, has been charged in federal court with kidnapping the family's two youngest children and killing one of them. Federal prosecutors are seeking the death penalty.

The federal trial was originally scheduled to begin this week, on Tuesday. At a hearing on Monday, prosecutors asked for a three-month delay, while Duncan's lawyers sought an 18-month postponement.

U.S. District Judge Edward Lodge ruled Thursday that the jury trial will begin Jan. 22, 2008.

Prosecutors say Dylan Groene, 9, was killed at a remote Montana campsite while his then-8-year-old sister Shasta Groene watched. Shasta was rescued July 2, 2005, at a Coeur d'Alene restaurant where Duncan was arrested.

The children's mother, Brenda Groene; her fiance, Mark McKenzie, and the younger children's 13-year-old brother, Slade Groene, were bludgeoned to death with a hammer during the May 16, 2005, attack. Duncan is already serving life in prison without parole for that attack.

The children's father, Steven Groene, had asked that the federal trial not be delayed too long. Suffering from larynx cancer, Groene said he wants to ensure that he is still around to support Shasta during what promises to be a difficult experience.

John Sahlin, a lawyer who represents Shasta's interests in court, also spoke in favor of the prosecution's shorter delay request.

Last October, Duncan pleaded guilty in Idaho's 1st District Court to first-degree murder and kidnapping for the three slayings at the family's home. A state judge sentenced Duncan to life in prison without parole for the kidnappings, but sentencing on the murder counts was deferred while the federal government prepared its charges.

If federal prosecutors fail to win a death sentence in their case, Duncan will be returned to the Idaho state court, where a jury will be impaneled for a death penalty hearing on the murder counts.

In January, Duncan was charged in a California state court in the 1997 abduction and slaying of 10-year-old Anthony Martinez in Indio, Calif. Prosecutors in that case said they also intend to seek the death penalty.

Duncan is also considered a person of interest in the decade-old slayings of two little girls in the Seattle area.