PRETORIA, South Africa Feb. 16, 2013 -- Oscar Pistorius is "numb with shock as well as grief" his uncle told reporters Saturday as the Olympian amputee spent his second night behind bars in a South African jail for the allegedly killing his model girlfriend Reeva Steenkamp.
"All of us saw at firsthand how close [Steenkamp] had become to Oscar during that time and how happy they were," he said. "They had plans together and Oscar was happier in his private life than he had been for a long time," said Pistorius' uncle Arnold Pistorius.
The 26-year-old athlete, known as the "blade runner" because of the carbon-fiber blades he runs on, was charged Friday with premeditated murder.
Pistorius' family is "battling to come to terms with Oscar being charged with murder," Arnold Pistorius said, and still believe "there is no substance to the allegation."
Oscar Pistorius is suspected of shooting Steenkamp, 29, four times with a handgun early Thursday morning at his home in a gated community in Pretoria.
Prosecutors dismissed the reports that Pistorious mistook her for an intruder.
If convicted, Pistorius could face at least 25 years in jail.
According to South African newspaper Beeld, Steenkamp was killed nearly two hours after police were called to Pistorius' home to respond to reports of an argument at the complex.
Police said they have responded to disputes at the sprinter's residence before, but did not say whether or not Steenkamp was involved.
A memorial service for Steenkamp will be held in Port Elizabeth on Tuesday evening, reported SABC. Her body will be flown back for the service before being cremated, her family said.
"Her future has been cut short...I dare say she's with the angels," said Mike Steenkamp, Reeva Steenkamp's uncle.
Producers of the South African reality show Steenkamp competed in said the series will still premiere Saturday night on SABC as planned, but will now include a special tribute to the slain law school graduate whose modeling career was starting to take off.
"This is the only time that you see the real Reeva," executive producer and director of "Tropka Island of Treasure" Samantha Moon told "Good Morning America." "She was kind and sweet and…so hard working.
"They will see the girl that we loved."
Meanwhile, the sprinter's sponsors – including Nike, BT, Theirry Mugler, Oakley and Ossur, the Icelandic company that manufactures the prosthetic blades Pistorius races on – are acting cautiously as the athlete awaits his bail hearing on Tuesday.
M-Net movies, a subscription-funded South African television channel has already pulled their ad campaign featuring Pistorius, tweeting, "Out of respect & sympathy to the bereaved, M-Net will be pulling its entire Oscar campaign featuring Oscar Pistorius with immediate effect."
Nike, who's ad featuring the double-amputee reads "I am the bullet in the chamber," released a statement saying the company is "continuing the monitor the situation closely."
Still, the athlete's' friends and colleagues said the murder charges have yet to sink in.
"When I heard, I was in shock and I'm just still trying to process it," Jamaican gold medal sprinter Usain Bolt told the Associated Press Friday night after the NBA All-Star celebrity game in Houston, Tex.
"I would just like to say, I have dated Oscar on and off for 5 YEARS, NOT ONCE has he EVER lifted a finger to me, made me fear for my life," his ex-girlfriend Jenna Edkins tweeted on Friday.
ABC News' Colleen Curry contributed to this report.