Plutarch, Comparison of Theseus and Romulus
Bernadotte Perrin, Ed.

Besides, there is dispute as to who actually slew Remus, and most of the blame for the deed is put upon others than Romulus; but Romulus did unquestionably save his mother from destruction, and he set his grandfather, who was living in inglorious and dishonourable subjection upon the throne of Aeneas. Moreover, he did him many favours of his own accord, and did him no harm not even inadvertently. Theseus, on the contrary, for his forgetfulness and neglect of the command about the sail, can hardly, I think, escape the charge of parricide, be the plea of his advocate ever so long and his judges ever so lenient. Indeed, a certain Attic writer, conscious that would-be defenders of Theseus have a difficult task, feigns that Aegeus, on the approach of the ship, ran up to the acropolis in his eagerness to catch sight of her, and stumbled and fell down the cliff; as though he were without a retinue, or was hurrying down to the sea without any servants.