A kiss goodbye, a trip to Walgreens and McDonalds... then found dead in her car three days later with her children alive beside her: Police probe bizarre sudden death of 'overwhelmed Texas model mom'

Frisco, Texas has been shocked by the death of local mom Christine Thi Woo, who was found dead in her car Thursday after going missing for three days. Her body was found alongside her three children who were severely dehydrated.

She vanished on Monday, along with her children Lauren Woo, 5, Nathan Woo, 3, and Leah Woo, 1. Her husband Brandon said she had disappeared on an ordinary day and described her as a 'rock' and a 'lioness'.

But locals who knew the woman say she seemed 'overwhelmed' and 'depressed'.

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Mystery: Christine Thi Woo (pictured, left) was found dead in her SUV in a SuperTarget parking lot at about 6:30 pm Thursday. Her children Lauren Woo, 5, Nathan Woo, 3, and Leah Woo, 1, were found alive by her side

Discovery: Pictured here is the SUV where Woo was discovered with her children. Her cause of death is unknown at this time but her body had no signs of trauma  

Quynh Chau, who runs a nonprofit called The Source of Hope, told WFAA 8 that Christine Woo had recently contacted her and seemed depressed. She said the mother had promised to attend an event to help the homeless but didn’t show up.

'She cried out to us and I could hear that in the sense of her voice,' Chau told News 8 hours before SUV was found. 'I wish so much that I could do something to reach out to her.'

And an employee of Frisco music school 7 Notes said to The Dallas Morning News that she seemed 'overwhelmed'. 

The Woos took their kids to 7 Notes each Saturday, where Christine would take Lauren for piano lessons while Brandon would accompany Nathan and Leah to baby and toddler classes. 

'She just loved her kids,' 7 Notes director Eileen Tan said. 'The whole family was into it.'

Tan described Christine Woo's enthusiasm for Lauren's piano lessons as 'gung ho' in an interview with CBS DFW Friday.

But Tan's executive assistant, Chardé Carbonell, said that Christine Woo's enthusiasm had waned dramatically since the kids enrolled in December.

She said the mom had talked to her on the phone for weeks gathering information before enrolling the children, but the parents' visits became inconsistent, and they would ask to 'take a break' or skip lessons.

'She seemed overwhelmed,' Carbonell said. 

Medical check: The three children were taken to the hospital for extreme dehydration after being found in this car. Leah was in critical condition Friday; all three children also had rashes from sitting in their own waste

But husband Brandon Woo, speaking to CBS DFW on Thursday while his wife was still missing, insisted there were no problems with their marriage and that she had no reason to run away from home. 

'She’s a loving mother, a great wife. She’s the most stable person you could ever meet,' he said.

He also told WFAA, 'She's like a lioness, she would fight for her kids, she would never hurt her kids at all.'

And in another conversation with the station, he said: 'She’s the rock of the family. She’s the most level head. I’m the one who gets emotional, always worried about finances or this and that. She’s the one that says, "We’ll figure it out."'

He also said that she was in 'good spirits and good health' when he saw her Monday morning and that he didn't know anything was wrong until he got home from work. 

'I kissed them goodbye as I always do, went out the door like I always do, come home that day and they were gone. Not there,' he told Fox.

'Got to the house, no kids, no wife, so I’m thinking, "OK they may be out at the playground, shopping, somewhere," so I give her a call, call her cellphone. Cellphone rings in the other room,' he told NBC5.

He told WFAA that Christine had left the house secured, without packing suitcases or even taking a bottle for their baby. 'She had every reason to come home,' he told the station.

'Lioness': 'Husband Brandon Woo described his wife as a 'rock' and a 'lioness' who was fiercely protective of her children. He also said she was 'the most stable person you could ever meet'

Christine Woo's body was found in her SUV in the parking lot of a SuperTarget department store in the Dallas suburb of McKinney about 6:30 pm on Thursday.

Police spokesman Jeff Inmon says an autopsy will be conducted to determine how the woman died, though there were no signs of trauma on her body, according to the Dallas News. 

Information is expected to be released by the Collin County Medical Examiner next week.

Her three children were alive but suffering from extreme dehydration, and also a severe body rash from sitting in their own filth for days, CBS DFW said Friday.

The station also said one-year-old Leah was in critical condition. All three were taken to the Children’s Medical Center in Plano.

Brandon Woo had reported his wife and children missing on Tuesday afternoon, mistakenly believing that missing persons could not be reported for 24 hours. 

He had received text messages saying that Christine Woo had used her credit card at a Walgreens near her home. 

She was also seen on security footage at Walgreen's, and she and her children were later spotted on video at a McDonald's just across the road from the lot where her body was found.

Police said earlier in the week that the family does not have a history of problems nor did Woo have any known medical or mental issues. 

CCTV: Woo and her children were seen in surveillance at a Walgreens, pictured, near her home. They were later spotted at a McDonald's across the road from where her body was found

The Dallas Morning News spoke to friends and neighbors of the family, who said Brandon Woo is a quiet man and the 'breadwinner' of the home.

Conversely, Christine Woo was described as an outgoing woman who would help out people in the community, and had recently started attending a women's Bible study at Stonebriar Community Church.

'She was a very lovely person and a sweet soul,' Elle Bonner, who lives next door to the family, told the paper. 

The death of Woo hit the Frisco community hard. 'We are doing all we know how to do right now - a lot of prayer, tons of prayer,' Carol Spencer of Stonebriar told CBS DFW. 

She added that the church had sent Sunday school teachers to the hospital to be available for the children and their father. 'We’re doing all we can for this family. Such a sad situation for all of us. Our hearts are just broken.' 

Brandon Woo released a statement through the Plano Children’s Medical Center that read, 'Thank you for your thoughts and concern for the well-being of my family.

'We request that everyone please respect our privacy as we focus on healing.'

The Dallas News reported that Christine Woo, née Nguyen, was a Vietnamese-American from San Antonio who graduated from Texas A&M University in 1999 with a business degree.

She and her husband owned a home in the city for eight years until they sold it in 2014 and moved into a 3,350-square-foot home in a family-friendly neighborhood near McSpedden Elementary School in Frisco.

Errands: Woo was seen at this Texas Walmart and was also spotted at a McDonald's before being found dead days later in the parking lot of a nearby SuperTarget