In a story that has gripped Australian public attention, the child's mother, Keri Lane, a senior policeman's daughter who is now aged 30, has admitted to giving birth to three children between 1995 and 1999 without ever revealing her pregnancies to her family, her friends, or even her then-boyfriend with whom she was in a relationship for four years.

But while her claim to have placed the first and third children up for adoption has been found to be true, nobody knows what has happened to the other infant, named Tegan Lee Lane.

It is likely that Tegan Lane's existence would have remained unheard of if New South Wales (NSW) community services workers had not pressed Keri Lane to explain anomalies in adoption paperwork which indicated that she had given birth to a third child.

Lane denied that she gave birth to the infant but records at Auburn hospital, Sydney, showed that Tegan was born on the morning of 14 September 1996. Community service officers wanted Lane to explain why they could find no other documentary evidence to support the child's existence. Community services staff became suspicious of Lane's denials.

But despite the community workers' concerns, which emerged in 1999, police in the district of Manly, where Lane is from, showed little interest in the case. A police probe did not get under way until May 2001, and soon afterwards, the officer in charge of the case was transferred. It seemed that Lane would get off the hook.

It was not until 2003 that a comprehensive police probed began, under detective constable Robert Gaut of Manly police. The NSW state coroner John Abernethy's report last week was critical of the fact that the lapse in assigning an officer to lead the investigation meant over 18 months passed between Lane's first and second police interviews. Gaut declined to comment on delays in the investigation, when contacted by the Sunday Tribune last week.

Lane has given police several different accounts of what happened to the child. She first told police in 2001 that she gave the child to its natural father, a man she named as Andrew Morris. She later said his surname was Norris. She said that since handing Tegan over to the man, she saw the child and the man once more, in Sydney in 1997. Lane told police in 2003 that she has not seen Tegan or the man since September 1996.

Detectives have found no trace of an Andrew Norris, or Morris, who fits the profile given by Lane.

Despite an extensive search of over 86,000 state records, no trace has been found of any registered birth that could correlate to Tegan.

What is most surprising, however, is that none of Keri Lane's friends or family were ever aware that she was pregnant three times.

Former Canterbury rugby player Duncan Gillies, who was her partner for over four years from 1994 to 1998, told the inquest that he didn't notice a thing. It was, he said, "a hell of a shock" to learn that a woman he lived with and had intimate relations with was pregnant twice during their relationship.

Gillies, who returned to give evidence from his present home in Ireland, said he and Lane would regularly have sex "spoon-style" and she was reluctant to let him embrace her. She was normally gone from their bed when he woke in the mornings.

"I understand how it looks, " he said. "It seems common sense that I would pick up on her having a baby. I wasn't skulking around in the dark to see if the woman I loved was having babies out the back door."

DNA testing has proven that Gillies is not the father of either the first or third child. No blood samples were taken of baby Tegan before Lane brought her from the maternity ward, so it cannot be established if Gillies was Tegan's father. "I could have a daughter somewhere. That never leaves my mind, " Gillies told the inquest.

Former friends, as well as swimming and hockey team-mates, told the police that they never knew that Lane had had three full-term pregnancies during the four years.

The inquest was ultimately unable to bring any clarity to the case. Abernethy was faced with the prospect of deciding definitively whether Tegan Lane is alive or dead. He could not.

"There are factors going to the proposition that Tegan Lane is alive, " Abernethy said. "The fact that there is no forensic evidence of death; the fact that she entered into the adoption process with both the first and third child; the possibility of Tegan living under an assumed identity."

But he noted that there are also pointers that Tegan Lane is dead. "These include the fact that Tegan Lane has not been seen since she was in Auburn District Hospital just after birth; the multiplicity of versions and untruths given to a range of persons; the initial denial of giving birth to the child at all." On the final claim by the child's mother that she gave her to her natural father, he said:

"I am completely unable to accept the final version given by Keri Lane". Abernathy concluded that he is "comfortably satisfied that Tegan Lane is in fact deceased".

Keri Lane's lawyer, Mary Bova, has gone so far as to issue a public appeal asking for the man her client knew as Andrew Norris to come forward. A spokesman for Bova said Keri Lane would be making no further comment.

What may happen next is anyone's guess. Abernathy has ordered that a full transcript of the inquest proceedings be forwarded to the NSW homicide police. But without a body and in the absence of any strong evidence, few are hopeful that Tegan Lane will ever be seen or heard of again.