WYANDOTTE, Okla. (AP/CBSDFW) — A North Texas mother is heartbroken after losing two children in a car crash and a third child is in critical condition.

It was supposed to be a new start for Erin Sanderson and her five children.

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Over the Thanksgiving holiday, the Garland family was to move to Carthage, Missouri to be with Sanderson’s boyfriend, Willis George.

But just 45 minutes out from their destination, the trip was cut short tragedy by tragedy.

Sunday afternoon, Erin’s boyfriend was driving her Ford Mustang with three of her children inside.

They were headed eastbound on Highway 60 in Oklahoma en route to Missouri, when state troopers say he suddenly crossed the center line and veered into oncoming westbound traffic.

Erin and her other 2 children were following behind in a rented moving truck and saw the entire accident unfold.

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CBS11’s Sharrie Williams spoke with Erin Sanderson by phone today.

“I thought, ‘oh my God please don’t let him hit that car,'” said Sanderson in the phone conversation. “I knew right then when they collided there’s no way anybody could have survived that crash.”

The family car struck a pick up truck head on.

39 year old George died at the scene, as well as Sanderson’s 14 year old son Drake Cobb,  and 13 year old Syrenna Sanderson.

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The passenger of the pickup, 19-year-old Samantha Delamatter of Fairland, Okla. also died in the crash.

“Syrenna was just the sweetest child.” said Sanderson. “Everybody loved her. She never met a stranger.”

Drake and his sister Syrrena went to school at Garland’s Jackson Technology Center for Math & Science.

Drake’s great grandmother Dorothy Whitaker says he loved electronics and wanted to design computer games one day.

“That’s what he had asked for Christmas was a real good computer,” said Whitaker. “My daughter and I went in together and bought him a real nice one for Christmas. Now he won’t get to use it.”

State Troopers in Oklahoma are still looking into why George crossed into on-coming traffic

The only child to survive the crash is 7 year old Maryssa. She’s in critical condition at a Missouri hospital with two broken legs.

“I’m trying to stay strong for my other daughter, said Sanderson. “I’m still in shock.”

The family has set up an account with Chase Bank to raise funds to transport the children back to Texas and to plan funeral arrangements.

It’s under “Drake & Syrenna Fund” Account number 3019735090.

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