GWYNN OAK, Md. — "We need to make sure we know who our kids are associating with."
Those are the words spoken by Baltimore County Police Chief Robert McCullough after a Gwynn Oak mother discovered her two children shot to death inside their own home.
Keith Maurice James, 16, has since been arrested and charged for the July 7 murders of Giovanna Myrie, 15, and her 9-year-old brother, Steve Allen.
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Their mother told police she left home for work at approximately 7am, and last spoke to Giovanna via text message around 4 that afternoon.
Upon returning home after 7pm, is when both children were found dead. Giovanna was shot multiple times in her bed, while Steve was left lying near the hallway.
A witness later told detectives that Giovanna had recently started talking to Keith.
The two reportedly met up at Giovanna's house on July 4th, at which time they chatted with the witness over FaceTime.
According to charging documents, the witness recalled seeing Keith holding a gun while in bed with Giovanna.
At some point during the conversation the witness heard Keith tell Giovanna, he'd have to kill her if she "messed around with any other guys."
A search of Giovanna's cell phone corroborated that account, as investigators recovered a message sent to the witness stating "Keith said if I cheat he finna put the gun inside me. Help Me."
The witness also placed Keith at Giovanna's house on the day of the murders, because the two were scheduled to meet up that evening.
After obtaining Keith's phone number, police pinged his call history and location near Giovanna's home on Talles Road the night she was killed.
A combination of MTA bus and area surveillance footage showed Keith getting off at a stop about half-a-mile from Giovanna's around the same time he called her phone.
After the murder surveillance footage showed Keith leaving Giovanna's neighborhood along a different bus route, but this time with a mask and hood on yet wearing the same headphones, shorts, and bookbag as before.
Investigators later interviewed Keith, who admitted to knowing and seeing Giovanna on July 4th. He denied having met with her on the night she was murdered.
Despite this denial, police believe the cell phone records and surveillance footage is enough to prove Keith killed Giovanna.
He's now charged as an adult and is due in court for a bail review on Thursday at 1pm.
