Chevoy Brown will never forget her son's first word. At seven months, Jarrod reached out to her, opening and clenching his hand. He was saying 'light' in Auslan - the sign language his parents had been using constantly around him since he had been diagnosed profoundly deaf a month earlier.
Ms Brown rejected the offer of a cochlear implant, concerned that if it failed to boost Jarrod's hearing sufficiently for him to acquire spoken English, he would miss crucial stages in language-related brain development that occur in early childhood.
Today, Ms Brown says, her conversations with the gregarious seven-year-old are every bit as sophisticated as those she had with her hearing daughter at the same age.
But Jarrod's first language could die out within half a generation, according to new analysis - a casualty of changing patterns of deafness and a trend towards deaf children attending mainstream schools.
This is actually fairly sad. AusLan is a distinct language, not signed English. Its grammar is radically different. Languages with shrinking use communities do not have a stable future.