Westbury toddler Luke Tibbetts' killer Lindray Khakhu was on Friday sentenced to life in prison by the High Court in Johannesburg, sitting in Palm Ridge.

"You are sentenced as follows... count seven, the murder of Alton Mooi, life imprisonment... Count 16, murder of Luke Tibbetts, life imprisonment," Judge Matthew Klein said.

Khakhu, 22, was also found guilty of nine counts of unlawful possession of a firearm and ammunition, four counts of attempted murder, the dangerous use of a firearm, and pointing a firearm.

Three-year-old Tibbetts was shot in the head in Steytler Street, Westbury, Johannesburg, on August 2 last year. He was sitting on his mother's lap in a car as Khakhu shot at Keenan Mokwena, who was travelling in another car.

Mokwena was wounded. Tibbetts died in hospital six days later.

Khakhu shot Alton Mooi dead in June 2013.

"I suspect that his motives were to show his greatness, power play and not caring what happens to others," Klein said.

"Today there is a mother who asked where is my three-year-old boy now? Come home my sweetheart," Klein said, summarising the evidence in aggravation of sentence.

"Unfortunately when one looks at the offences that were committed, they were all by their very nature, very serious, serious crimes. There is no crime that is more serious than the taking away of another person's life, particularly in a constitutional democracy as ours."

During sentencing proceedings, Tibbetts' uncle, Llewellyn Valentine, sobbed with his head on his arms in the first row of the public gallery.

Khakhu, looking serious and wearing ankle chains, briefly spoke to his family over the dock before being led away by police. His sister, Lindsey Campbell, ran out of the court room crying.