Passage 1.9.1
ὁ δὲ Φιλομήτωρ καλούμενος ὄγδοος μέν ἐστιν ἀπόγονος Πτολεμαίου τοῦ Λάγου, τὴν δὲ ἐπίκλησιν ἔσχεν ἐπὶ χλευασμῷ. οὐ γάρ τινα τῶν βασιλέων μισηθέντα ἴσμεν ἐς τοσόνδε ὑπὸ μητρός, ὃν πρεσβύτατον ὄντα τῶν παίδων ἡ μήτηρ οὐκ εἴα καλεῖν ἐπὶ τὴν ἀρχήν, πρότερον δὲ ἐς Κύπρον ὑπὸ τοῦ πατρὸς πεμφθῆναι πράξασα· τῆς δὲ ἐς τὸν παῖδα τῇ Κλεοπάτρᾳ δυσνοίας λέγουσιν ἄλλας τε αἰτίας καὶ ὅτι Ἀλέξανδρον τὸν νεώτερον τῶν παίδων κατήκοον ἔσεσθαι μᾶλλον ἤλπιζε. καὶ διὰ τοῦτο ἑλέσθαι βασιλέα Ἀλέξανδρον ἔπειθεν Αἰγυπτίους·
The one called Philometor is the eighth descendant from Ptolemy, son of Lagus, and received this title in mockery. For we know of no king who was so deeply hated by his own mother. Although he was the eldest of her sons, his mother refused to summon him to the throne. Earlier, she had even arranged that his father send him away to Cyprus. As regards Cleopatra's hostility toward her son, other causes are mentioned, and especially that she expected greater obedience from Alexander, the youngest of her children. For this reason, she sought to persuade the Egyptians to accept Alexander as king.