A woman who allegedly abandoned her three-month-old baby girl at a Brisbane share house before heading to the Brisbane International Airport is being questioned by police.
The infant was found on the front porch of an inner-city Herston home, by PhD student Long Nguyen just after midday on Sunday.
Mr Nguyen said he was on the way to university and was shocked to see the baby in a capsule.
"I really didn't know what was going on, it took me a few minutes to calm myself down," he told the Seven Network.
He took the baby inside and waited for police.
Australian Federal Police said a 41-year-old woman was seen in a vehicle being driven erratically at the Brisbane International Airport precinct later on Sunday.
"AFP members stopped the vehicle and spoke with a 41-year-old woman, who was accompanied by a two-year-old child," a spokeswoman said.
"The matter was referred to Queensland Police."
Queensland Police could not confirm reports the woman was recorded as a missing person after concerns from the woman's husband, who hadn't seen them for more than 24 hours.
The baby was taken to the Lady Cilento Children's Hospital for observation, while the woman was taken to the Prince Charles Hospital for a health assessment.
Queensland Health could not comment on the matter other than to say the baby was no longer in the hospital and referred all questions to the QPS.
The QPS media unit said it had no update on the matter and the woman was helping with inquiries.