The Austin High School junior was shot in the face, and police still don't know who did it or why.
When her mother, Sherri Johnson, first found out about the shooting, it was described as a suicide. Then, the medical examiner ruled it a homicide.
Johnson said they're asking for more testing, because Swain may have been pregnant.
"One was already bad enough, but if she was (pregnant), it would be even more devastating," Johnson told Eyewitness News on Thursday.
Swain's grieving mother said she still can't comprehend what happened to her daughter, and possibly her grandchild, at an apartment in Alief last Saturday night.
"I never ever thought she would die tragically. She was loved by many," she said.
That love was on full display in November 2010. Eyewitness News cameras captured Swain's family adopting her at 4 years old.
"I feel like a kid on Christmas. This is a gift. A lifetime gift," Johnson said at the time.
That lifetime turned out to be a short 17 years, and Johnson said things weren't always easy.
Swain struggled with mental health, but she had aspirations of joining the military and was just beginning to turn her life around.
"Sometimes they fall down and get back up again," Johnson said. "She stumbled quite a bit, but she didn't deserve to die tragically and brutally like that."
Houston police are looking into her death as a homicide and are asking the public for information that could help them find the shooter and figure out their motive.
Those are details Johnson said would give her strength as she fights for justice.
"They say I'll get through it. It's going to be extremely hard. Where you see one of us you, would see the other. That was my ride or die," she said.
Teen killed in area rare for homicides
ABC13's Neighborhood Safety Tracker found a comparatively low rate for homicides in the area where Swain's killing took place.
Only one homicide was counted in the last 12 months inside the designated Catalina Square-Bellaire West-Imperial Point area, which is where 25,000 people reside.
In addition, one homicide was counted in 2019, three each in 2020 and 2021, and just one in 2022.
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