Philo Judaeus Legatio Ad Gaium 62

But after Macro and all his house had been sacrificed, Caius then began to design a third more grievous piece of treachery still. His father-in-law had been Marcus Silanus, a man full of wisdom, and very illustrious by birth. He, after his daughter had died by an early death, still was very attentive and affectionate to Caius, showing all imaginable regard for him, not so much like a father-in-law as like an actual father, and he hoped that he should find that Caius also entertained equal good will towards him, transforming himself according to the principles of equality from a son-in-law into a son; but he was, without knowing it, cherishing mistaken opinions, and deluding himself,