Drew Peterson's son testifies before grand jury

Drew Peterson's 15-year-old son has testified before a Will County grand jury investigating the 2004 death of his mother, Kathleen Savio, and the Oct. 28 disappearance of his stepmother, Tracy Peterson.

Thomas Peterson gave his testimony Thursday.

For months, the grand jury has been investigating the death of Savio, who was found dead in an empty bathtub only weeks before her divorce from Peterson would have become final. Her death was originally ruled an accident, but authorities reopened their investigation after Peterson's fourth wife, Stacy, disappeared and Peterson was named a suspect in that case. In February, Will County State's Atty. James Glasgow said Savio had been murdered.

Drew Peterson said by phone Thursday that he was concerned that the grand jury had been grilling his son for four hours