Susan Rank, 30, was booked for murder after investigators determined she was responsible for the death of her daughter. The victim was identified by family members as 3-year-old Zayla Rank.
The child's grandmother and great aunt told Eyewitness News that Susan Rank is mentally ill and they believe she is responsible for her own daughter's death.
Susan Rank was born with a brain tumor and suffered mental illness all her life, according to her aunt Tracylyn Sharrit.
Sharrit doesn't blame Rank. She says she blames the system.
"When a 3 year-old becomes collateral damage of somebody else's mental illness, we as a society have to say what is broken in this system?" Sharrit told Eyewitness News. "Zayla couldn't protect herself. Susan couldn't protect her either. She was mentally gone."
She says Rank had been reaching out for help, but the Riverside University Health System couldn't do anything for her. She was given medication, but it didn't help and she returned again and was given a pamphlet for sober living homes.
Rank was already living with her daughter in a sober living home associated with the group Set Free Ministries, her family members said.
Susan Rank's mother, Lori Wood, said she tried hard to get her daughter some help. Now, she says, she feels as if she's lost her daughter and granddaughter on the same day.
"It took everything I had as her mother to get her to go into those doors to ask for help in the first place," Wood said. "And she did it. And they still sent her away. And it killed me to wake up this morning to see it didn't work."
The Riverside health system said it couldn't comment on the case because of patient confidentiality laws.
Authorities were first alerted to the incident with a phone call around 6:45 a.m. Friday.
Sheriff's deputies responded to a home in the 3400 block of Cannes Avenue and discovered the girl's body outside the residence.
Authorities told Eyewitness News that everyone at the house was immediately detained, including the homicide suspect, and no one else is being sought.
"Interviews are starting right now, and it's just one of those sad days where we have to report this," said sheriff's Deputy Mike Vasquez.
The family has started a fundraising effort to help pay for Zayla's funeral expenses.
"Our family is heartbroken," Sharrit wrote on the GoFundMe page. "My sister is in deep mourning over the loss of her grandbaby, and the fact that it was at the hands of her mentally ill daughter weigh heavy on her heart."
Asked to comment on mental illness as a possible factor in the case, Vasquez responded: "We're looking into the possibility of those things. We never are going to rule one of those out, or that out, but we really haven't established that at this point."
Officials asked anyone with information about the case to contact Investigator Ted Gonzalez with the Central Homicide Unit at 951-955-2777 or Jurupa Valley Investigator Mike Barros at 951-955-2600.