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FRISCO (CBSDFW.COM) – A Frisco mother found dead with her children alive in their SUV bought sleeping pills before her death, according to a source.

A security camera at Walgreens recorded Christine Woo, 39, and her children shortly before they disappeared Monday. The discovery of Woo’s body and her children has left many wondering what could have led to the tragedy. How did the children survive up to 72 hours? Why didn’t the 5-year-old get out? And if their mother committed suicide, why would she put her children at risk?

These are some of the many, many questions left unanswered; questions Frisco Police are trying to answer. And as the investigation continues, the community has come together in support of the Woo children.

Candles lit up Warren Park in Frisco where several dozen people held a vigil organized by Frisco Mom’s Care.

“It touched our hearts, she’s a mother just like we are. We just wanted to be able to show support and say a prayer for her children,” said Ariana Trimmer of Frisco Mom’s Care.

Many who attended the vigil don’t know the Woo family but simply wanted to show that they care.

“I think every mother, every parent that has heard of the story has played out in their imagination what happened in that car,” said Cate Biggs with Frisco Mom’s Care. “If there’s a mother out there that is having a hard time she needs to know that this is a community supports her.”

Woo’s cause of death was undetermined at the time of this report. The result of an autopsy being conducted by the Collin County Medical Examiner is expected early next week.

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