1. I think he gave up US citizenship in Indonesia, when he was adopted.
2. He comes back to the USA, and needs Papa Obama to vouch that he did not approve of the adoption or dropping of US citizenship or Kenyan Citizenship, so that Soebarka can stay in the USA. His Mother needs the sign off, because, technicaly, Soebarkah Obama Bin Laden is still a born Kenyan citizen, with all such rights.
If the Kenyan Father says, no, he did not give permission, then the adoption and Indo Citizenship is not recognized as lawful. Getting the little Indo-muzzie-jihadist back into the states required his Kenyan fathers participation.