Sibusiso Khanyi successfully sued for negligence last February after he was born at Pholosong Hospital, East Rand, with cerebral palsy on December 2 1999.
Interest was charged at 15.5% a month on the R9.25-million awarded by the Johannesburg High Court.
Another late payment by the office of Premier Nomvula Mokonyane has added R320000 in interest to the R6.25-million payment due to Shabbier Nagel, who had a leg amputated when he went for heart surgery at Steve Biko Academic Hospital in Pretoria.
Nagel has been promised that he would get his money on Friday.
Mokonyane's office was granted leave to appeal the Sibusiso court decision, which lapsed on July 22.
Mokonyane's office on Monday decided to abandon the appeal and pay Sibusiso and his family.
"They have made a fair offer," said their lawyer, Gary Austin, adding that he could not reveal details of the agreement.
Sibusiso's mother Martha said she was happy her family would get the money soon as it would change their lives for the better.
DA health spokesman Jack Bloom said yesterday: "This is a real fiasco as this money could have been saved if Premier Nomvula Mokonyane had taken the sensible decision earlier not to pursue an appeal that was likely to fail.
"Her legal advisers are utterly incompetent because they allowed their appeal to lapse, and then scrambled for condonation even as the sheriff arrived to remove goods from the premier's office [on January 18]."
He said someone in Mokonyane's office should be "held accountable for this mess".