The in-laws of Josh Powell called for change Thursday in how Washington state protects children.

Their grandsons, Charlie, 7, and Braden, 5, were killed Feb. 5 by their father, Josh Powell, who also killed himself in his rental home during a state-approved visitation. Josh Powell was also a person of interest in the disappearance of his wife, Susan Cox Powell, in Utah in 2009.

“I had a very strong feeling that something bad was going to happen that day,” said Judy Cox, Susan’s mother and the boys’ grandmother. “I  knew we had to follow the law, because that’s the right thing to do.”

Judy and Chuck Cox had temporary custody of the boys at the time.

“Clearly there should not have been visitation in a private home,” added Chuck Cox. “If  that was necessary, there should have been more safeguards.”

They've teamed up with state Sen. Pam Roach, R-Auburn, who wants to block murder suspects from getting custody or visitations with their kids.

But in the Powell case, it wouldn’t have made a difference; he was a person of interest in the disappearance of Susan Powell, not a suspect.

Meanwhile, the Department of Social and Health Services released a statement announcing who will sit on the panel to review the circumstances around the deaths of Charlie and Braden Powell, who were killed by their father Josh Powell on Feb. 5.

Josh Powell attacked the children, ages 7 and 5, with a hatchet before blowing up the house, killing all three of them.

Washington state law requires a review when a "child death or near-death injury is suspected to be caused by abuse or neglect, and the child has received services from Children's Administration in the previous 12 months," the statement said.

Josh Powell was denied custody of his children at a Feb. 1 hearing. The children had been in the temporary custody of Chuck and Judy Cox, the parents of Susan Cox Powell, Josh's wife who has been missing since December 2009.

At the Feb. 1 hearing, the judge ordered that Josh Powell undergo a psychosexual evaluation based in part because of his father Steven Powell's arrest for having pornographic images on his computer (he is currently in Pierce County Jail) and Josh and his sons lived with Steven at the time, and because hundreds of pornographic images had also been found on Josh Powell's computer.

Since the deaths of Charile and Braden Powell, DSHS has come under scrutiny for allowing Josh to continue having supervised visits with his sons.

DSHS is required to complete the review within 180 days following the death of a child. The panel will convene April 26-27 to conduct a review and a neutral, outside party will act as co-faciliitator.

The panel includes King County Prosecuting Attorney Rich Anderson, Tacoma police detective Brad Graham, Sen. Randi Becker (R-Eatonville), Sen. Jim Kastama (D-Puyallup), Judge Jim Doerty and other members with backgrounds in psychology, domestic violence and children's welfare.

The panel will publish the review upon its completion.