He said the charges had initially been dropped, only to be reinstated later.
It was the second time the Pistorius case was weighed down by additional charges.
South African police appointed a new chief investigator last Thursday, replacing a veteran detective after unsettling revelations that the officer was charged with seven counts of attempted murder.
Oscar Pistorius was charged with premeditated murder, but the athlete says he killed his girlfriend accidentally, opening fire after mistaking her for an intruder in his home.
On Saturday, the family took steps to lower its profile on social media after someone hacked into the Twitter account of Carl. They cancelled all the social media sites for both Oscar's brother and his sister Aimee.
Carl has always been close to Oscar but was notably absent when their uncle Arnold, flanked by Oscar's sister Aimee, read out a first reaction to the shooting on Feb. 17, even though he was also on the premises.
The three-story house where Pistorius is staying with his aunt and uncle sits on a hill with a sweeping view of Pretoria. It has a large swimming pool and an immaculate garden.
The character of Pistorius also continued to take center stage. For many, it mirrors his public appearances as an articulate, well-spoken advocate for Paralympic athletes facing hardship. Witness statements backing up Oscar Pistorius as a down-to-earth guy were presented at the hearing.
Others have described him as a reckless risk taker who has been in trouble before, such as a boat accident in 2009 which put him into hospital intensive care unit.
On Sunday, a South African man who said Steenkamp had stayed at his home since September, described Pistorius as moody and impatient. Cecil Myers, whose daughter was close friends with Steenkamp, said in an interview published Sunday in the City Press newspaper, that Pistorius will have the killing of Steenkamp on his conscience. "I hope he gets a long sentence. Gets what he deserves," said Myers.