A top cop turned TV crime expert is praying Aisling Symes has been taken by a "nutty woman".
Retired Detective Inspector Graham Bell, who hosts TV2's Police Ten 7, said he hoped and believed she had not been taken by a sexual offender, because she was last seen with a young woman.
"If that is right, it would augur well for the child being looked after, because that raises the possibility of a nutty woman who may be pining for a child."
He was also fascinated by the description of the mystery Asian woman as wearing socks and sandals "which in our society is regarded as a little bit eccentric.
"It could suggest she's a recent immigrant - it's an odd way to dress in Auckland's climate."
Ernie Allen, president of the United States National Center for Missing and Exploited Children, said time was the enemy for police hunting for Aisling.
If she had been abducted, the culprit may have made up a story for family or friends to explain the presence of an unknown child in their life.
"Somebody knows, and will reach out to authorities with information, but they likely will not do that if we don't prod them."
Allen said abductions of very young children were less likely to be sexually motivated, and in most cases the child was unharmed.
"In the United States most of the abductors of infants and newborns are women, usually emotionally disturbed women, who are seeking a child to keep a relationship alive or for some similar reason," he said.
"The big challenge with a very young child is that they are easily manipulated by abductors. They believe what they are told. If they are told that they are supposed to be wherever they are, they tend to believe it."
Allan said he had high regard for New Zealand police, who would be doing everything possible to find her.
"They are first-rate, among the best in the world, and I am confident that they are on top of it," he said.