Sandra Bland Had 'Lows and Highs,' Her Sister Says

— -- The relatives of the woman found dead in a Texas jail cell three days after being pulled over in a traffic stop are grappling to make sense of her arrest and death.

Sandra Bland, a 28-year-old activist who had posted a series of videos online before her July 10 arrest in Texas, had said in one of the videos that she suffered from depression and post-traumatic stress disorder.

But her sister says Bland may have made the claims to connect with her audience online.

"I think everybody has lows and highs and I think that, you know, she was having maybe a bad day that day," Bland's sister Sharon Cooper told ABC News today.

"You know, I have to reiterate that the totality of that video does show that she was leaning more towards an inspirational perspective at the end and had remnants of hope and it was really just a way for her to share with the mass audience, you know, what she was feeling and letting them know that if they were too struggling, that there was a light at the end of the tunnel," Cooper said.

Cooper went on to say that her sister had "absolutely not" been treated for depression or been diagnosed with the illness.

Depression and PTSD were not the only alleged medical issues that Bland had mentioned in the past. The dashboard-camera recording from Bland's arrest also shows her warning the officer that she has epilepsy.

Bland's medical history has come under scrutiny as investigators try to answer why she allegedly hanged herself in a jail cell July 13 using a plastic garbage bag liner.

Cooper confirmed that her sister had a miscarriage in May 2014. Bland had written on a jail intake form that she had tried to kill herself at that time, using pills, though Cooper was not specifically aware of that incident.

Bland's relatives are awaiting an independent autopsy report and though they have not seen the final results, Cooper said the preliminary results "show that she did have deep-tissue bruising to her back which is consistent with the officer having his knee in her back."

Cooper said the autopsy is just one of the things she and her family hope will provide answers.

"I have to tell you I am very, very concerned on behalf of my family,” she said, “and I’m just, just astounded.”

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