Just a few hours earlier, she'd been the image of perfection. Now, her beautiful white dress had been cut open and paramedics were putting a breathing tube down her throat. 'She's alive but unconscious,' one told me as I looked on in total shock.
Soon, Sarah was being rushed to Alfred Hospital. I stayed with her while Dennis, Biddy and Scott followed. Rushed to intensive care, Sarah was placed into an induced coma as doctors ran tests.It was hours before I fully understood what had happened. 'Sarah's heart stopped suddenly,' the doctor told us. 'We're still looking for the cause.'
He went on to explain that two ladies from the venue performed CPR on our girl before the paramedics arrived. Their quick thinking had kept the blood flowing to Sarah's brain. But shockingly, her heart hadn't been restarted until paramedics used a defibrillator on her four times. Now, Sarah's body was being cooled to help her brain and body recover. It was just so scary for us all.
'The speeches were on and we were about to eat dessert when she collapsed,' Scott recalled. 'I thought Sarah was just leaning on me at first.' In fact, my girl had been unconscious, so he and a friend had carried her out of the hall before calling for help. Up until that moment she'd been fine. None of us could understand why this happened
The next day, with Sarah still unresponsive, the doctor had devastating news. 'If she wakes up there's a chance she'll have permanent brain damage,' he said, explaining she had suffered cardiac arrest - which is where the heart stops beating without warning.
Six months earlier, Sarah had suffered chest pains and tests revealed a leak in one of her heart valves. It's a genetic condition - one that Tess and I share. We'd been assured that it was nothing to worry about.
Most people with the condition live their whole lives without realising. But did it cause Sarah's heart to stop? The doctors didn't know. In the days that followed, our family rallied round, taking it in turns to sit beside Sarah's bed.
Two days later, as we headed to her room, a nurse had great news. 'Sarah opened her eyes,' she told us. It was the first in a chain of miracles. Later that day, Tess, Biddy and their brother David, 23, were sitting by her bed when Sarah squeezed her sister's hand. Then her eyes flickered open.
'Everything's okay,' I soothed as tears streamed from her eyes. It was overwhelming, but each drop was to be celebrated because it meant she was slowly coming back to us. She started breathing on her own and gradually we were able to speak to her.
But Sarah had great trouble remembering what had happened. She didn't recall the school formal at all. Not wanting to overload her, I printed some photos of her in her dress and stuck them in albums she could flick through.
Even so, it was tough. Most mornings, Sarah would forget everything we'd talked about the previous day. One day, Scott was visiting when Sarah smiled and reached for his hand. 'Hi,' she managed. She was glad to see him but it took a while for Scott to convince her they'd been to his formal.
While medics still didn't know if Sarah's heart condition led to what happened, 10 days later they fitted a tiny defibrillator into her chest so that if her heart stops again it'll immediately be restarted.After a week of physio, she was fit enough to come home.
Now it's been three months since the formal, and it's only recently that Sarah's fully understood what she's been through. I kept her torn white dress and while looking at it is hard, it has helped us both come to terms with what happened.
Sarah is now doing well and is back at school - although her memory is still patchy. Next year, I'm glad she'll get to go to her own formal. After everything she's been through, I'll make sure she has a heap of happy memories from that special day.
Sarah, 17, says...
The last vague memory I have is getting picked up from school to have my make-up done - sadly, the rest is a blank. I'd really been looking forward to Scott's formal and was feeling completely fine, so it's really scary to have lost all my memories of the night.
That's why I'm thankful to have so many photos that are helping me piece together the puzzle. I'm still coming to terms with what I've been through but with the support of my amazing family and boyfriend I know I'll get there.