Pay overstay fine on Christmas Day.

HI all,I previously overstayed in Brazil and left in 2015. My wife is Brazilian and our kids were born there and we are returning for a holiday in a few weeks time. We will arrive on Christmas morning in Sao Paulo airport and I need to pay my fine for overstaying. As the banks wont be open,does anyone know how I would go about this.
Any help would be greatly appreciated.

PF will have agents at the airport. You did not mention type of visa.They will either reduce the days allowed or you pay the fine. There are agents at the payment offices. May have longline so be prepared.

Your last visit was in 2015.  The immigration laws have had a complete overhaul since then, and the Federal Police computer systems have had at least one major system migration.  It's likely that the records of your fine were not migrated.  When you come through Immigration,  if they don't bring it up, you're home free.