The Broward County Sheriff's Office said Monday Angela Divin was improving at the Broward Medical Health Center, The Miami Herald reported.
The shooting happened about 7 p.m. Saturday inside the siblings' home in Oakland Park, the South Florida Sun-Sentinel reported.
"The siblings had been home alone when the teen found the handgun," sheriff's office spokeswoman Dani Moschella said in a release.
Moschella said it appeared the brother, whose name had not been released, accidentally pulled the trigger, but police were still investigating.
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