BRUNSWICK, Ga. -

The defense attorney for a 17-year-old accused of killing a Brunswick toddler filed a motion suggesting the murder was not a random act of violence, implying that a key witness in the case was somehow involved.

Kevin Gough, attorney for De'Marquise Elkins, filed a motion asking for "disclosure of any and all 'deals' made with material witnesses ... and known associates of Debra Obley," the great aunt of the second defendant: 15-year-old Dominique Lang.

Obley (pictured below) told Brunswick police she gave Elkins a ride from his mother's home, claiming she didn't know he had just killed 13-month-old Antonio Santiago. Her tip to police led to a series of arrests in the case.

In his motion, Gough suggests Obley was more than a concerned citizen, but may have been involved in a possible murder-for-hire or insurance fraud.

DOCUMENT: Motion for discovery

Obley talked to Channel 4 two days after the slaying, saying she became suspicious when Elkins lay down in the back seat after getting into her car and was acting nervous. She claimed she came forward despite knowing that people might retaliate against her.

"I'm being threatened by people saying they are going to kill me or have people to kill me because I'm a snitch," said Obley at the time.

Elkins and Lang (pictured left, in first court appearances) remain in the Glynn County jail held without bond on murder charges.

Elkins' mother and sister, Karimah and Sabrina Elkins, 36 and 19 respectively, were also arrested on charges they disposed of the gun used to kill the toddler in a saltwater pond a couple miles from where the boy was shot and his mother injured March 21 while walking in a historic Brunswick neighborhood.

Pictured:
Karimah, Katrina and Sabrina Elkins

Police say Karimah and 33-year-old Katrina Elkins, the teen's aunt, also created false alibis for De'Marquise Elkins at the time of the shooting.

Investigators said De'Marquise Elkins shot the child in the face while trying to rob the boy's mother as she pushed him in a stroller.

"Very scary that it could be a target murder on my son, and I think they actually tried to kill me, too," Sherry West, Santiago's mother, said Wednesday. "And I believed from the beginning it was not random, just for money."

West said she does not know Obley and that there was very little insurance on her child. West is still recovering and  says she is worried about an upcoming bond hearing for those charged in this case. She said cards have come in from across the country, and she is thankful for the support.

"I'm hanging in there. I mean, I cry every day. And my baby, we miss him a lot," West said.

Glynn County Police Chief Matt Doering said there could be more arrests, depending where the evidence leads investigators. He said more physical evidence was collected and ballistics tests would be conducted on the gun, but due to saltwater damage that could take 30-45 days to complete.