Res Gestae

Then, on hearing that Julian had been raised to the eminence of an Augustus, having small hope or none at all for his life, he became afraid and tried by distance to avoid the dangers that he suspected. So, abandoning all his family, he left and came by slow stages to Constantius, and to show his guiltlessness of any fault, he assailed Julian with many charges

After his departure, Julian, considering the matter well and wisely, and wishing it to be known that he would have spared him even if he had been present, left his dear ones and his property unmolested, gave them the use of the public courier-service, and bade them ride in safety to the Orient.