He made the call in a statement welcoming a Supreme Court of Appeal judgment on Madiba's Qunu home.
Seipei was a member of the Mandela Football Club who was 14 when he was killed.
Doctor Asvat was shot dead in his Soweto clinic.
The SCA earlier dismissed Winnie Madikizela-Mandela’s latest legal bid for her former husband's Qunu home.
She challenged Madiba’s decision to leave the home to his third wife, Graca Machel, and her children.
The court dismissed Madikizela-Mandela’s appeal on the grounds that there was an unreasonable delay in instituting legal action.
Madikizela-Mandela was implicated in Seipei's death but has consistently maintained her innocence.