Laisha Perez begged her mother to stay at her friend's house on Saturday evening, according to her family members. A few hours later, she was found shot to death.
ABC13 law enforcement sources identified the suspect as 38-year-old Humberto Valdez-Saldana. According to the sheriff's office, he shot and killed his girlfriend's two daughters and sexually assaulted her 12-year-old daughter. Laisha, a friend who just happened to be there, was also shot.
READ MORE:12-year-old saves baby after mom's boyfriend kills 3 teens in murder-suicide in Galena Park: HCSO
Her family held a fundraiser on Tuesday as they were forced to come up with funeral expenses for Laisha.
Her cousin, who is the same age, spoke on behalf of the family with her parent's permission.
"She was so happy. Even when she was sad, she always put a smile on her face," Yoselyn Romero said.
Laisha was in 9th grade, loved to paint, and left behind four siblings.
Her family said she would be remembered for her contagious smile.
"It wasn't fair what happened," Romero said.
The family created a GoFundMe to help with funeral expenses.
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WATCH: Sources identify man accused of killing 3 teens in murder-suicide, sexually assaulting another
Sources identify man accused of killing 3 teens in murder-suicide, sexually assaulting another