Scribonia, wife of Augustus, mother of his daughter Julia, was NOT Fulvia's daughter, nor Gaius Scribonius Curius' daughter. Scribonia was the daughter of Lucius Scribonius Libo and Cornelia. Augustus' first wife was Clodia, daughter of Fulvia; Scribonia was his second wife; Livia the third and... last wife.

Suetonius' "The Life of Augustus", 63:
[...] he took to wife Antony's stepdaughter Claudia, daughter of Fulvia by Publius Clodius, although she was barely of marriageable age; but because of a falling out with his mother-in-law Fulvia, he divorced her before they had begun to live together. Shortly after that he married Scribonia, who had been wedded before to two ex-consuls, and was a mother by one of them. He divorced her also, "unable to put up with her shrewish disposition," as he himself writes, and at once took Livia Drusilla from her husband Tiberius Nero, although she was with child at the time; and he loved and esteemed her to the end without a rival.

We know that Suetonius was not totally accurate, but I doubt that he would make a mistake about that.

Suetonius, The Lives of the Caesars, in Lacus Curtius http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Suetonius/12Caesars/Augustus*.html