The dark, painful past, designer Alannah Hill says she is always drawn back to.

If you’ve been impacted by sexual assault, domestic or family violence, 24-hour support is available. Please call 1800 RESPECT.

Among the earnest, monochromatic shows at Australian fashion week, Alannah Hill‘s runway was a burst of colour and energy. Her models had hips and breasts, they smiled, winked, and danced down the catwalk in her floral, flirty designs.

“It drives people mental,” the designer told Mamamia’s No Filter podcast. “If I do anything I have to do it bigger, louder more incredible. I need to have fun.”

But behind it all was something much darker, more painful.

At the age of 12, while on a train to her grandmother’s place in Hobart, Alannah was sexually assaulted by her 15-year-old brother.

“I’m always amazed how much abuse sexual abuse can affect someone. You can cut a baby, you can leave a 12-year-old on the side of the road for hours. But sexual abuse cuts to the core of something that’s unexplained; it’s indescribable,” she said.

That ongoing trauma, a desire to mask it, plays out in her aesthetic - both professional and personal. Her face is always made, her hair rolled - "If [my hair] starts to fall flat, I start to feel young, like a child again, like I did when I was small... I feel very vulnerable."

On her runways, it was in the designs, the staging, the choreography, even the casting of the models.

"If you were a psychiatrist [you would have known]. I'd think, 'Is anyone going to pick this up?' Because the dancers would come out and do this incredibly flirtatious [act]," she said.

"They had mirrors that they'd be looking in, they'd be brushing their hair, the songs would be kitsch - it'd be an ABBA song that had got me through my childhood.

"And I had signs at the back of those parades saying 'At the end of the catwalk, don't do that pouty thing, blow a kiss or pull your skirt up a little bit. Just show off, show that you have got the power, that you are incredible and you are so desired by everybody.' And I found that very empowering for them."

On one occasion, she directed legendary Czech model, Eva Herzigová, to pretend she was being chased down the runway.

"Even now I think I've got the image of her, the video of her running down the catwalk looking behind her," Alannah said. "And she did look a bit peculiar. But I realise now I made her do that because I was scared, I was scared to look behind me, so I got her to do it."

Now that she has moved on from her the label that bears her name, Alannah is finally looking back - at her work, at her childhood, and that one "colossal" event when she was 12 - via her book Butterfly on a Pin.

"It never really leaves," she said. "But I'm not defined by the abuse - I'm really not. If something where I feel powerless happens in my life, it's just like elastic time. I'm always drawn back in time to that one event. And everything else is alright, everything else is okay around me, but that one event..."

Still, she doesn't blame her brother for any of it.

"I know that he would have had no idea the impact of what he did would have on me, because there were so many other things going on in that family home that were so diabolical that I don't think he knew anything else," she said. "He just snatched the rest of my pathetic childhood out of my heart, and that there was not a lot left."

If you've been impacted by sexual assault, domestic or family violence, 24-hour support is available. Please call 1800 RESPECT.

Alannah shares more of her incredible story on No Filter...

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