"I heard a loud bang in the car and I hit the brakes... I thought something had exploded in the car," said Kanita Thomas at Lindray Khakhu's trial in the High Court in Johannesburg sitting in Palm Ridge.
"[Luke's mom] Candice was shouting 'Oh Lord Jesus they shot my son'.
"I turned around and I looked at him and I saw blood."
Thomas struggled to contain her emotions as she explained how she then rushed straight to a hospital.
She recalled how Steytler Street in Westbury, Johannesburg, was very busy on the night of the shooting.
On August 2 last year Khakhu allegedly shot at a white car another man, Keenan Mokwena, was travelling in in Westbury.
Tibbetts was in Thomas's car with his family travelling in Khakhu's direction as Khakhu allegedly shot at Mokwena's car while it drove off.
A stray bullet hit the car's windscreen and struck Tibbetts in the head.
He died six days later in hospital.
The court heard on Wednesday that Tibbetts had been sitting in the centre of the back seat of the vehicle, on his mother's lap.
Khakhu is on trial for two murders including that of Tibbetts, five counts of attempted murder, 10 of unlawful possession of a firearm and ammunition, and one of pointing a firearm. He has pleaded not guilty to all charges.
