Sixty-eight-year-old Lenore Matusiewicz waived a detention hearing in Wilmington on Wednesday and pleaded not guilty. A judge ordered pretrial motions to be submitted by Oct. 15.
Matusiewicz's daughter, 41-year-old Amy Gonzalez, faces a detention hearing Thursday on similar charges.
Matusiewicz and Gonzalez are the mother and sister, respectively, of former Delaware optometrist David Matusiewicz. All three are charged with conspiracy, interstate stalking and cyberstalking involving David's ex-wife, Christine Belford.
David Matusiewicz's father, Thomas Matusiewicz, fatally shot Belford and her friend, Laura Mulford, in February before exchanging gunfire with police and killing himself.