HOUSTON - It's being called a family murder plot in two "honor killings." Four people are now charged in connection to the death of an Iranian student and her friend.
On Tuesday, Nadia Irsan walked shackled into a Harris County Courtroom and listened to prosecutors read their case against her.
"Numerous instances of stalking behavior, of stalking trips," said Tammy Thomas of the Harris County Prosecutor's Office.
Irsan is charged with stalking her sister, Nesreen Irsan, after Nersreen left their father's home to marry a Christian man, Coty Beavers.
Their father, Ali Irsan, is Muslim. Prosecutors call him controlling and domineering, and they say he murdered Coty, and Nesreen's best friend, Gelareh Bagherzadeh, because he thought she helped convert his daughter to Christianity.
In court Tuesday, prosecutors said Nadia also threatened Coty before his murder.
"At one point made the comment, I cannot wait until my dad puts a bullet between your eyes, to Coty Beavers," said Thomas.
Nadia is accused of putting a GPS tracker on her sister's car and driving around her home.
"Almost consistently on a daily basis was encircling the apartment complex," said Thomas.
Prosecutors say the GPS showed Nadia taking that route, up until the day Coty Beavers was murdered in the apartment he shared with Nesreen in November 2012. The GPS was later found buried at the Irsans' house.
Ali Irsan's wife and son are also charged with helping him commit murder and the prosecutor said Tuesday Nadia Irsan could possibly face more charges in the future.
Nadia Irsan and her parents are also accused in a separate federal fraud case. The judge has withheld bond for Nadia, saying the federal case needs to be resolved first.