Claims that one of the founders of the PAC, Robert Sobukwe, received preferential treatment during his incarceration on Robben Island were "borne out of anger", his son said this week."My father was in Robben Island. He served his sentence. There are many people who served in many prisons with him who are alive and can tell a better story. If he was given preferential treatment, he would not have missed his family," Sobukwe's son, Dini Sobukwe, told News24.He was reacting to comments made by the SACP's Solly Mapaila on Tuesday at a dialogue celebrating the Rivonia Triallists at Liliesleaf Farm in Rivonia."It is unfortunate to think about isolation only. He suffered a lot while in isolation. Mapaila's remarks were borne out of anger. I don't understand his thinking. I don't know where his utterances came from."Sobukwe said he did not know what had angered Mapaila."We need to find out why Mapaila said what he said. It is shocking that those words came from a progressive leader. Clearly, we don't need to respond to such statements by Mapaila. It is unfortunate and I don't think they deserve a response from someone."He added that, if the SACP's deputy secretary general read about his father, "he could have a better idea".Better privilegesEarlier on Wednesday, IOL reported that Mapaila had described Sobukwe as someone who was favoured by the apartheid regime.He claimed that the anti-apartheid activist was treated as the only political prisoner on Robben Island, while others were regarded as terrorists.Mapaila was the main speaker at Tuesday's dialogue, which was held to celebrate the 29th anniversary of former statesman Nelson Mandela's release from prison.He reportedly told those in attendance that he was airing his views for the first time.On Wednesday, when asked about his claims by a reporter from broadcaster eNCA, Mapaila stood by what he said and added that he blamed the apartheid government for this and not Sobukwe."They put him in a house. He was treated as the only political prisoner while others were treated as terrorists and slaves and were condemned to hard labour in Robben Island. All over the world it is known. Political prisoners are treated better. The worst criminals are condemned."That is what happened to our leaders in Robben Island. They were crushing stones every single day in the quarry. Robert Sobukwe had privileges. He could receive clothing, he could receive books, he could have a radio, he had a whole house to himself, although he was in isolation."Mapaila also claimed that those who were treated as terrorists were punished because they supported the Communist Party, and were regarded as communists.