Three new floats in the parade would carry "special guests" for the children, organiser Malcolm Dodds said.
The city's single biggest event is expected to attract about 40,000 people.
Mayor Peter Chin has invited his grandchildren down from Wellington to join him in greeting the crowd.
Organisation of the parade began in August.
On the day of the parade, 180 children and 100 adults will man the floats.
The parade will leave the University of Otago Dental School at 3pm on Sunday and travel along George St to the Octagon.
It will be followed by two concerts at 4.30pm - the Mayor's Carols with the Southern Sinfonia at the Regent Theatre and a family concert with Bill Acklin's band in the Octagon.