JOHANNESBURG, South Africa -- The mother of the South African woman killed by athlete Oscar Pistorius says she does not care about an upcoming appeal.

Pistorius' lawyers will challenge a judge's decision to allow prosecutors to appeal later this week the runner's negligent killing conviction.

June Steenkamp, the mother of Reeva Steenkamp, who was killed by the Olympian, said on Tuesday the appeal does not matter to her even if it led to a harsher sentence for Pistorius.

Steenkamp was announcing plans to launch a foundation against domestic violence in Reeva Steenkamp's honour. She would not be drawn into questions on whether she believed her daughter was a victim of domestic violence.

Pistorius shot Steenkamp, his girlfriend at the time, in his home in South Africa's capital Pretoria on Feb. 14, 2013.