Meghan Lippiatt won't be hearing the otherworldly voices anymore.

At least not on this side.

The body of the 35-year-old Lancaster County woman, who killed her two young sons seven years ago, was found Saturday in a minivan at the bottom of 500-foot-deep canyon on an Arizona Indian reservation, possibly two months after a fatal plunge.

Lippiatt was found not guilty by reason of insanity in the the 2004 suffocation of 4-month-old Miles and the bathtub drowning of Silas, 2, his hands zip-tied, at her home in Mount Joy. At a 2007 trial before a county judge, testimony reportedly described her hearing the voice of God and "dark voices" and believing the boys were possessed by demons.

Police found the children after an anonymous caller - apparently Lippiatt - told a 911 dispatcher, "I did something really bad. I just killed my kids."

She spent more than three years in jail and a state psychiatric hospital before the judge agreed with the insanity defense and set her free in late 2007.

Authorities in Navaho County, Ariz., are investigating Lippiatt's death as a possible suicide, according to the Lancaster Intelligencer Journal's website.

She was last seen alive in Lancaster County in February, according to the account.

In September 2008, Lippiatt discussed getting treatment, said she was "not a monster," and described feeling haunted. "I have to live every day with that loss and knowing that it was me that caused it," she said.

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com.