Community services have removed a six-week old boy from the care of his parents after the child was left alone in his capsule on a street in Lidcombe in the early hours yesterday.

The infant, found by police about 3.15am, was taken to The Children's Hospital at Westmead to be treated for the effects of the cold. The child's parents were found a short time later at Lidcombe train station, following a report to police of a man and woman arguing.

Minister for Community Services Pru Goward said after 24 hours of assessment, her department had decided to remove the child from its parents.

"Today we decided that we would, at least temporarily, remove that baby," she said. "Information we received today makes us confident that the best option, the best way of keeping this baby safe, is to remove it from its parents."

The minister would not comment on whether there were previous reports to child protection services about the welfare of the baby but said the department did not have information to suggest the child was at risk of being abandoned.

Twin toddlers found wandering

Ms Goward said her department was also talking to the family of toddler twin boys who were found wandering along a street in south Sydney this morning, wearing just nappies and shirts.

The boys, believed to be aged about two, were found walking along Lysander Avenue, Rosemeadow, about 9.30am today by a local resident.

The minister said the circumstances leading to that incident were very different from the baby found at Lidcombe and the family's issues were believed to be "resolvable".

"We are still assessing the safety of that family, we are talking with that family now about the plans they might have to put in place to ensure that their children, their two-year-old children, are supervised at all times," she said.

The twin boys had not been previously reported to community services.

Ms Goward said the latter case should serve as a warning to parents about the need for close supervision of children.

"If you have young children - and toddlers are very mobile - you need to remember that if you can't supervise your children, it's important to put in plans so that someone else can," she said.

According to figures provided by the government, there were 276 reports of children being at risk of significant harm, where the primary reported issue was child abandonment, during 2010-2011.

Anyone who believes a child is at risk of harm (in NSW) can report to the Community Services helpline on 132 111.