From single mum to poster girl: How this mum-of-five lost 19 kilos

We chase bad guys.

It's what we do at A Current Affair and we're pretty good at it. We go in to bat for those who can't for themselves, we don't shy away from the big yarns, and yes, we love a supermarket savings story.

But every now and again, we come across a story -- a person -- who really touches us. 

Kay is a single mother of five children. Her entire focus is her kids, she loves them and she wants the best for them. She's a devoted mum.

As you can imagine, five kids has kept Kay pretty busy for a pretty long time, meaning she hasn't had any 'me time' in 20-something years. 

I was looking for women who may be interested in taking on a fitness challenge as part of an ACA story. We were planning on putting three different celebrity fitness regimes to the test. 

Here at ACA, we have an inbox where viewers can submit stories or offer themselves up as talent. That's how I came across Kay.

I called her and asked her whether she'd like to do Michelle Bridges' 12 Week Body Transformation, filming her journey and her results.

Daunting, right? Not for Kay. She couldn't wait to embrace the challenge. She even called it a blessing in disguise.

So Michelle Bridges, my camera crew and I went off to meet Kay. She greeted us with a beaming smile and I could instantly tell she was going to give this challenge all she has.

So back we went to film the follow-up story on the set of Michelle Bridges latest TV commercial. That's right, Kay is now a poster girl!

"The only thing I can say is I feel like I'm living now. I'm actually living the life I'm supposed to be living," Kay told A Current Affair. 

"So I was very hopeful that I would actually lose some weight but I had no idea the journey that I would be going on. The things that have opened up to me in the last couple of months because of the way I've been feeling with inside myself, feeling positive. I've been attracting positive people towards me and positive experiences."

Kay even brought Michelle Bridges to tears.