Her lawyer/husband killed both her and her son by giving each of them methadone while they were on antidepressants, the mixing of the two causing death. He effectively got rid of the two heirs to the cash (between 50 and 450 million supposedly) so he can control the money.

That is why he is blocking the paternity test by the other guy, because he is listed as the father and he knows that a test will reveal the other guy as the real father. Also, in the Bahamas the name listed on the birth certificate is officially recognized as the father so that is why baby was taken to Bahamas when she died. It will be a long court battle but as of right now lawyer/husband will control the money if he gets away with it.