GREENSBORO, N.C. (WGHP) – A North Carolina mom could face the death penalty after police say she shot and killed three people Wednesday morning.

Brittany McKinney, 28, faced a judge for the first time on Thursday; she didn't say a word during the brief hearing.

McKinney's sister and mother told WGHP it's an extremely difficult and tragic time for the entire family.

Investigators say McKinney shot and killed her 10-year-old daughter Mkenzie and 2-year-old niece Serenity. She's also accused of killing 61-year-old Jerry Griffin, who was living with the family on Sweet Birch Drive in Greensboro.

"She said, 'I killed everybody. I shot everybody in the house,'" said Delilah Merritt, McKinney's sister. "She's like, 'My baby, my baby, I shot my baby.' And then I said, 'Where's Serenity?' and she said, 'I shot her too.'"

That's when Merritt called for a welfare check on McKinney's home.

"I never thought she would do something like this," she said.

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Lisa Campos and her daughter Laila still can't believe what happened a few houses down from them.

"They would play in the front of my house and stuff," Campos said.

Neighbors Laila and Mkenzie rode the bus together to George C. Simkins Jr. Elementary School.

"We just became friends and she was really nice to me," Laila said. "I'm going to miss her."

A small mailbox makeshift memorial has popped up outside of where tragedy struck. There, friends and neighbors have put up pictures, cards, flowers and a bundle of purple balloons.

The grieving process for family and friends is only just beginning.

"I didn't want to believe it," Merritt said. "I still don't."

Merritt told WGHP she thinks her sister was just overwhelmed with life and it just became too hard for her.

Guilford County Schools will be providing crisis counselors for students at Simkins Elementary School on Friday.

McKinney is being held without bond and is expected to be back in court on Monday.