"It was a miracle," she said, her voice quivering with emotion after a year.
Entombed in broken steel and mortar, she was unaware of her injuries - fractured pelvis, gashed leg and concussion.
She could see smoke overhead.
"I thought the stairwell was going to fall and I could see smoke. I thought we had survived the collapse and now were going to be killed by smoke or fire.
"I tried to remove the rubble over our heads. My foot was pinned, and I managed to free that but the rest was too heavy.
"I heard someone walking above me and I yelled out. He told us we were okay, that he'd get us out.
"I held on to the kids and pretty quickly a gap opened up above us. I just remember seeing this guy's face [Evan McLellan], and the rest was a bit of a blur."
Twelve months on, the hairdresser still looks back on that day with a mixture of wonderment, grief, and shock.
She had taken Jett to the fifth floor of the CTV building to undergo counselling for anxiety brought on after the September earthquake.
"Aftershocks hit our house like a freight-train," Ms Mitchell recalls. "Jett just couldn't cope. He wouldn't sleep in his room, [he was] clingy, and had severe anxiety."
They were waiting to see the counsellor when disaster struck.
"It was extremely violent. I grabbed Jett, and Dita was in her buggy at my feet. It seemed to go on and on, and we were getting thrown left, right and centre.
"The internal east wall started to disintegrate from the top and I thought it was a dream for a second, and then I knew it was real, and I thought we were all going to die. There was this massive sucking sensation - I felt we were being sucked down and the building [was] staying in place."
Ms Mitchell was discharged from hospital within hours on February 22, and her partner Hayden Lamont, 30, drove the family to Timaru, for sanctuary with relatives, and to recover.
Jett has recovered from his anxiety, is back sleeping in his own bed and starts school next month.
"He is doing great," his proud mum, who is still undergoing rehabilitation, says.
"We all are, really. It's been a traumatic year, but we're getting there and we now look at life totally differently. I still suffer a bit of anxiety, but I cherish life.
They will return to Christchurch today after nominating Mr McLellan for a Christchurch Earthquake Award.
- APN