Fairfield Woman Behind Bars After Police Say She Stabbed Her Sister to Death

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FAIRFIELD -- Holding a family photo, Steve Cobb can hardly believe it's now the only way he'll be able to hold his baby sister Mary Douglas and that the person police say took her life at a Fairfield home is a sister to them both.

"Everything was OK till yesterday. I don't know what might have snapped in her head or transpired, but she's been dealing with mental issues for a long time," said Cobb.

Cobb wasn't there when something went wrong inside the home Douglas shared with her mother, sister Zena McDuffie and sister Antoinette Clay.

In his regular pattern of checking on Clay, he'd had no indication tragedy was near when they spoke.

"She said, 'Brother are you coming to see me tomorrow?' I said, 'yes' and I said 'yes...I'll be right out there first thing in the morning,' So I said, 'OK I'll see you in the morning,' and that was the last that I'd heard from her," said Cobb, remembering Clay seemed chipper, her normal self.

But police say the abnormal happened on Valencia Drive, three and a half hours later with Clay grabbing a knife and stabbing her two sisters in the middle of some kind of fight -- killing Douglas.

She's now behind bars at the Solano County Jail.

According to Cobb, 44-year-old Clay has struggled with paranoid schizophrenia since she was 18, spending time in and out of mental hospitals, the last just a few months ago.

"She'd stopped taking her medication, saying she didn't need it," he said.

Known to call 911 herself if she felt she was losing control, Cobb doesn't understand why Clay didn't do that Monday.

Thinking of one sister he's lost his heart is full.

"Mary, oh man, sweetest sister in the world. Um, big into church. She loves God."

Thinking of the other sister now lost to the system, his heart is heavy.

"We should all take mental illness very serious because you never know," he said.

"We're a very close family so this is just very bizarre, and it just goes to show you nothing is ... nothing is promised."

Antoinette Clay is on mental health watch at the jail.

Her sister, Zena McDuffie, remains hospitalized as a result of her wounds from the fight.

Cobb says if it wasn't for McDuffie's actions during the fight, their mother might have been gravely injured.

He's still confused about what issue set Clay off in such a destructive way.