First, it was the clothes Ella's parents noticed. The little girl would tell her parents nothing fitted quite right; she wanted her shoes and clothes to feel "tighter".
For her birthday, the six-year-old asked for Barbie dolls, and pink, sparkly clothing she'd noticed other girls wearing. But the dolls were left in the drawer, and the clothes went unworn. What was going on?
Their daughter made good eye contact, and she could hold a spirited conversation, says Ella's father, Luke Bibby. But if her routines were disrupted, or circumstances led to sensorial overload, Ella would have a meltdown.
Girls are more adept at camouflaging or "masking" autism than boys, and copying the behaviour of their peers to fit in.
Ella had been pretending to love Barbie dolls because she'd decided that was what society expected from girls.
When she was diagnosed with autism spectrum disorder, all this suddenly made sense to her worried parents. But many girls like Ella miss out on diagnosis or are diagnosed much later in life.
The core symptoms of autism are the same in males and females, but how it manifests is often different, says Professor Nicole Rinehart, from Monash University.
"There's not enough research funding in this area, point blank," Professor Rinehart says. "Most research studies are about boys, we don't have enough concentration on girls."
Ella loves cars and motor racing, and her parents have encouraged her to pursue her passion. Photo: Stefan Postles
A recent online survey of almost 2000 families found more than 50 per cent miss out on early intervention. The poll was commissioned by autism advocacy group Yellow Ladybugs.
More than 70 per cent of people don't know the number of females diagnosed with autism has increased, says Fiona Sharkie, the head of Amaze, the peak advocacy group.
The core symptoms of autism are the same in males and females, but how it manifests is often different. Photo: Stefan Postles
"Acknowledgement of women and girls on the spectrum – how it presents, the specific nature of autism in girls and their unique challenges – needs more exposure," said Ms Sharkie.
Through sessions with her psychologist, Ella's parents finally realised it was not dolls that fascinated their little girl, but cars and motorsports.
When she was younger, Ella pretended to love Barbie dolls because she thought that was what society expected. Photo: Stefan Postles
Keen to give his young daughter a figure to aspire to, Luke Googled the terms "female car mentor Australia". And this was how Ella and her family discovered Molly Taylor, 28, Australia's first female rally driver.
They took Ella to far-flung rally events to see Taylor race. At first Ella would be rendered speechless when Taylor came to say hello. She once told her parents she hoped Taylor knew she was yelling "go Molly" inside, even though the words didn't come out.
Taylor and Ella have formed a special relationship, and the sportswoman wrote recently in a Facebook post: "I remember when Ella's Dad sent me the picture of Ella working on a car, my heart melted! Since then I've been able to meet Ella at many of the rallies. The future for women in motorsport is looking bright!"