BRUNSWICK, Ga. – The mother of a baby gunned down in his stroller says she has no doubt a teenage suspect is the man who killed her 13-month-old son, but a family member says he wasn’t anywhere near the scene.

“That’s definitely him,” Sherry West said Saturday when she saw the jail mugshot of 17-year-old De’Marquise Elkins, who is charged as an adult with first-degree murder. Police also arrested a 14-year-old who has not been identified because he’s a minor.

“We’re trying to determine which one actually was the shooter,” police spokesman Todd Rhodes said Saturday.

But West said she was certain the gunman was the older suspect. “He killed my baby, and he shot me, too,” she said.

On Thursday morning, West was pushing Antonio Santiago in his stroller. She said a teen, accompanied by a smaller boy, asked her for money.

One of the teens fired four shots, then walked around to the stroller and shot the baby in the face. Police announced the arrests of Elkins and the 14-year-old Friday afternoon. But Katrina Freeman, Elkins’ aunt, said Saturday that he couldn’t be the killer because the two were together at the time of the shooting. Freeman said Elkins dropped by her home about 8:15 a.m. — roughly an hour before the shooting — and she cooked them grits, eggs and sausage for breakfast.

They stayed at her home until about 11 a.m., Freeman said, and then Elkins accompanied her and her children on some errands for about an hour. After noon, he left for classes he’s taking to earn his GED, she said.