Peterson's Children to Testify at Grand Jury

Two of Drew Peterson's children from his marriage to Kathleen Savio have been subpoenaed to testify in front of the grand jury investigating his possible involvement in her death and the disappearance of his fourth wife, Stacey Peterson, ABC News has learned.

The two boys, Tom, 15, and Christopher, 13, were served with subpoenas Wednesday and were granted immunity in return for their testimony. They are currently living with their father.

A coroner's inquest had previously ruled the 2004 death of Savio, Peterson's third wife, an accident, but an autopsy report last week determined that Savio was killed in her Bolingbrook, Ill., home, a few weeks before her divorce from Peterson was complete.

Peterson, a former Bolingbrook police officer, has not been named as a suspect in Savio's death, but he is considered a suspect in Stacey Peterson's disappearance. Authorities reexamined Savio's death after Stacey Peterson disappeared in November.

Drew Peterson has denied any wrongdoing in both cases.

For years, Savio's relatives have suspected Peterson of being involved in her death, telling the 2004 coroner's inquest that Savio was terrified of her former husband, whom they said threatened her and hit her.

"We've been waiting for this," Savio's sister, Anna Doman, told ABC News. "We didn't think it would ever happen."

Now, in an exclusive interview with ABC News Senior Law & Justice correspondent Jim Avila, a juror on the coroner's inquest that initially determined Savio's death was an accident says he wishes he had listened to her family.

"If we would have come back with murder instead, maybe Stacey Peterson would still be here today," Jim Pretto told ABC News. "There is a little bit of guilt that because of that, maybe somebody else was murdered because of that. That maybe could have been stopped."

Savio was found facedown in the empty bathtub of her home on March 1, 2004, a few weeks before the property settlement from her divorce from Peterson was scheduled to be finalized. She had a one-inch gash on the back of her head.

An autopsy at the time of Savio's death found that she had drowned and speculated that she may have slipped and hit her head on the tub. A state police officer testified at the inquest that there was no evidence that Savio had been murdered.

Pretto faulted investigators for failing to present enough evidence at the inquest and said that if he had known all the facts about the case in 2004, he would have called Savio's death a homicide.

"There was no evidence at all to point toward it being a murder," Pretto said. "There was nothing presented at all."