Passage 9.5.9
κατὰ δὲ τὴν τιμωρίαν τοῦ Ἀμφίονος ἔστιν ἔπη ποιήσεως Μινυάδος, ἔχει δὲ ἐς Ἀμφίονα κοινῶς καὶ ἐς τὸν Θρᾷκα Θάμυριν. ὡς δὲ τὸν οἶκον τὸν Ἀμφίονος καὶ Ζήθου τὸν μὲν ἡ νόσος ἡ λοιμώδης ἠρήμωσε, Ζήθῳ δὲ τὸν παῖδα ἀπέκτεινεν ἡ τεκοῦσα κατὰ δή τινα ἁμαρτίαν, ἐτεθνήκει δὲ ὑπὸ λύπης καὶ αὐτὸς ὁ Ζῆθος, οὕτω Λάιον ἐπὶ βασιλείᾳ κατάγουσιν οἱ Θηβαῖοι.
There exist verses composed by Minyas concerning the punishment of Amphion, a subject shared in common also with Thamyris the Thracian. After a plague had made utterly desolate the house of Amphion and Zethus, and the son of Zethus had been slain by his own mother because of some fault, Zethus himself also died from grief; accordingly, the Thebans brought back Laius to assume the kingship.