SUETONIUS, Life of Augustus
[LXIV] Nepotes ex Agrippa et Iulia tres habuit C. et L. et Agrippam, neptes duas Iuliam et Agrippinam. Iuliam L. Paulo censoris filio, Agrippinam Germanico sororis suae nepoti collocavit. Gaium et L. adoptavit domi per assem et libram emptos a patre Agrippa tenerosque adhuc ad curam rei p. admovit et consules designatos circum provinciasexercitusque dimisit. Filiam et neptes ita instituit, ut etiam lanificio assuefaceret vetaretque loqui aut agere quicquam nisi propalam et quod in diurnos commentarios referretur; extraneorum quidem coetu adeo prohibuit, ut L. Vinicio, claro decoroque iuveni, scripserit quondam parum modeste fecisse eum, quod filiam suam Baias salutatum venisset. Nepotes et litteras et natare aliaque rudimenta per se plerum que docuit, ac nihil aeque elaboravit quam ut imitarentur chirographum suum; neque cenavit una, nisi ut in imo lecto assiderent, neque iter fecit, nisi ut vehiculo anteirent aut circa adequitarent.
64. He had three grandsons by Agrippa and Julia, namely, Gaius, Lucius, and Agrippa; and two granddaughters, Julia and Agrippina. Julia he married to Lucius Paulus, the censor's son, and Agrippina to Germanicus, his sister's grandson. Gaius and Lucius he adopted at home, by the ceremony of purchase from their father, advanced them, while yet very young, to offices in the state, and when they were consuls-elect, sent them to visit the provinces and armies. In bringing up his daughter and granddaughters, he accustomed them to domestic employments and even spinning, and obliged them to speak and act every thing openly before the family, that it might be put down in the diary. He so strictly prohibited them from all converse with strangers, that he once wrote a letter to Lucius Vinicius, a handsome young man of a good family, in which he told him, You have not behaved very modestly, in making a visit to my daughter at Baiae. He usually instructed his grandsons himself in reading, swimming, and other rudiments of knowledge; and he laboured nothing more than to perfect them in the imitation of his handwriting. He never supped but he had them sitting at the foot of his couch; nor ever travelled but with them in a chariot before him, or riding beside him.