When dealing with children, they say to expect the "unexpected", but for one mom of 4 boys and first grade teacher, this day in May was something she could have never prepared herself for.

It was an ordinary afternoon when Karen Marinelli was teaching her class at Plaza Tower Elementary School in Moore, Oklahoma, when the heard the tornado sirens start waling.

An EF5 tornado, one of the most intense and destructive natural disasters was ripping a path for the small town.

In the line of fire was Karen and her students. The school took a direct hit from the tornado and it managed to rip apart the entire structure, with people still inside.

As many as 25 people lost their lives in the disaster and more then 350 people were reported injured.

No One Left Behind

There were kids screaming, glass breaking and an unforgettable roar, that Karen could only describe as a monster.

Karen refused to leave any of her students behind, when the sirens started to scream. She stayed in the hallways to help evacuate all the youngsters out of the building without any regard for her own life.

The situation went from bad to worse when a 2,000-pound car slammed into the brick wall right next to Karen. The car pulled the wall down and landed right on top of the teacher who was using her body to protect three 6-year-old students Liam, Damian and Dacari.

Find Out What Happened Next.

What's Left Behind

Amazingly all the children were completely unharmed, thanks to Karen's actions.

As a result of the accident Karen suffered a broken back, fractured vertebrae, sprained ankles, deep wounds and separated ligaments.

She spent the next 3 months in a wheelchair.

Recovery

The community, along with the families of Liam, Damian and Dacari banded together to help Karen recover from her injuries.

It didn't take long for donations to begin pouring in for her family. Boxes of water, supplies and food were given to assist the family in the tough time. One box, however really caught Karen's eye. It was filled with baby girl outfits and diapers.

As a mom of 4 boys ranging from 14-years-old to 5, the family had no intention of having another baby so she put the box aside to donate to another family.

What she didn't know was the package could actually be a sign of things to come.

New Addition

To her complete surprise, she became pregnant with a due date of May 20- exactly one year after the tragic tornado ripped through her small town.

Karen said, "Just seems like it was meant to be. I know she was meant to be. She was meant to be our blessing, definitely. I think she's going to wrap us up. A nice little bow, the topper on the cake."

Babies however, are as unpredictable as the Oklahoma weather. Lily arrived a little early. Lillian Claire was born a healthy 6 pounds 9 ounces on May 8, her name meaning "return to happiness."

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