At the time, two years ago, the family lived in Queensland.
Her son, a Qantas pilot, was recalled by the control tower as he taxied down a runway.
Colleagues could tell him nothing, but put him into a cab bound for home, where an hour earlier he had put his baby daughter, Scarlett, down for a nap and left her with her aunt.
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READ NOWKnowing it would take him time to get home, he rang his mother, who lived nearby.
Ms Allen arrived in her son’s street to find it full of police, paramedics and onlookers.
She does not remember getting out of the car, or what happened next.
She was since diagnosed with Post-Traumatic Stress Disorder, stemming from the shock of discovering 13-month-old Scarlett had died during her nap, a victim of Sudden Infant Death Syndrome (SIDS).
‘We had had a family party the night before and Scarlett was so happy, running around giggling and trying to sing Happy Birthday to her great-grandmother,’ Ms Allen said.
‘We never saw it coming.’
Ms Allen said the family had relied heavily on support from SIDS and Kids WA.
‘I never imagined I would need an organisation like SIDS, but without them having been there for us, I don’t know if we would have got through some of those darkest times,’ she said.