The next generation of Australia's most inbred family, who were discovered living on a filthy remote block in the hills of country NSW a decade ago, have begun asking questions about their past - including if one girl's father is also her uncle.

The 40-strong Colt family were discovered by authorities living without electricity, running water or sanitation near the town of Boorowa, 150km north of Canberra, in 2012.

Their story of incest, depravity and squalor shocked the world when authorities discovered the clan living in isolation on a filthy bush block in the hills, and the NSW Children's Court found the case so disturbing it decided to publish a lengthy judgment of its findings.

Choosing pseudonyms to protect the children, including Ruth Colt, the Court's unprecedented 34-page dossier on the family nevertheless contained horrifying detail of intergenerational incestuous behaviour and neglect conducted in secret for decades. 

Ruth, one of the youngest members of the family and now about 19, has surfaced on social media, posting about her loneliness, how she misses her siblings and directly questioning the man believed to be both her father and uncle.

'Hi,' she wrote to her dad on social media. 'Are you and mum brother and sister?' 

She then wrote, 'do you know who my dad is?' and 'hi uncle how are you'. 

Ruth's mother Martha and her aunt Betty were the matriarchs of the clan. The young woman was just nine when her family's terrible secret was uncovered by authorities, after a chance remark in the schoolyard by one of her siblings.