The baby's grandmother told ABC13 over the phone that the baby's mother didn't know she left the 2-month-old in the back of the car.
She says the mother thought she left the baby at home, while she and her 4-year-old went to the Harris Center for Mental Health and Intellectual Developmental Clinic.
Eyewitness News went to the clinic Wednesday afternoon and noticed a sign at the front desk warning people not to leave children behind in their cars.
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"Here's the thing, from time to time, we have incidents like this which should never happen, especially in the summertime. You should never leave a child unattended," Yasar Bashir, Houston Police Department assistant chief, said on Tuesday. "That's something we're going to find out. Was the child left intentionally? Or not. That's something we're going to have to look into."
ABC13 learned new details since talking to the police on Tuesday.
Investigators are now saying the baby is 2 months old, not 3 months, as originally thought. Right now, they are waiting for autopsy results to find out how the baby boy died.
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Authorities won't decide if anyone is charged until the medical examiner declares the cause of death. ABC13 also reached out to the communications team at the clinic, to ask if that sign at the front desk was put up before or after the baby's death.
A representative for the clinic, Nicole Liecsay, said they are looking into it and provided the following statement:
"We are heartbroken by this tragic loss of life. Thousands of people visit our clinics every year, but we have never experienced this type of tragedy. We extend our deepest sympathy and condolences to the family. Any additional questions should be directed to the Houston Police Department."
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The baby boy's grandmother was emotional over the phone and told ABC13 their hearts are aching.
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