Prosecutors filed their notice of intent to pursue the death penalty against Nicole Virzi in Allegheny County Court Thursday.
Sebastian, 15, who has medical conditions such as autism, was reportedly last seen on February 25 in Hendersonville, Tennessee, as his mother was putting him to bed.
The FBI is investigating the case with assistance from the Bureau of Alcohol, Tobacco, Firearms, and Explosives and the Alabama Law Enforcement Agency.
Wilson, 30, will learn his fate Tuesday, for the 2019 fatal strangulations of Cape Coral, Florida women Kristine Melton, 35, and Diane Ruiz, 43.
