On April 9, it was a feeling Joe Thomas never felt before. The 46-year-old from Frisco had just come in from outside working in the yard. His chest was tightening and he was having trouble breathing.

"I could tell something was off," said Joe Thomas.

His wife Angela and 12-year-old daughter Aerin were at a nearby Kroger when they got a phone call. They knew something was up because Joe normally texts and rarely calls. Once they arrived home they noticed Joe was in the bedroom.

"I just heard a gasp, a struggle for breath and he was gone," Angela said.

In the 911 call obtained by News 8 you can hear the panic in their voices. Their home had quickly turned into an emergency room. Joe was unconscious and Angela was attempting to do CPR. Aerin, their 12-year-old, was on the phone with dispatch.

"I vaguely remember [Aerin] saying something like 'you're not doing it right,' and she took over," said Angela.

Aerin quickly turned her attention to her father. Performing CPR after she had just learned it 3 months ago. The sixth grader at Cobb Middle School had taken the training in her P.E. class. CPR training is a mandatory part of the 6th grade at Frisco ISD since 2012.

"I just had chills. I'm retiring this year and it's the icing on the cake for me; the last really nice thing that's happened through a career," said Coach Kathy Barton.

Aerin had performed CPR for five minutes but she says it felt double that. She would continue until paramedics took over.

"I knew it was going to be...I was hoping it was going to be ok," said Aerin.

The following statement was taken from FISD Superintendent of Schools Dr. Jeremy Lyon:
“We are so proud of Aerin and her coaches at Cobb Middle School. We know CPR and AEDs can save lives and improve a person’s chances of survival and this is yet another example of FISD students and staff using their training and skills to make a difference. We are thankful for this outcome and the contributions of all those involved."

Joe is still a bit groggy but expected to make a full recovery. It was three days later that a father knew what his daughter had done: basically saved his life.

"Never take a day for granted. You never know what your last day might be," Joe said.