The event basically points to the events surrounding Suleyman and his son Mustafa, where despite Mustafa being the favored son he was still killed due to accusations from people in court, including the Sultan's high consort. The fact that this event is apparently firing for just about every heir (which I can't claim to have seen all that much myself since I've only played Coptic since 1.18 when playing the Ottomans, I've seen it maybe 2 times in the 8 or so early games I played) does seem like some kind of bug, or maybe there needs to be some kind of rules for it to fire.
Maybe make it so the event can only fire if either the Sultan or the heir's claim has 75% legitimacy, since the first would mean the son would have a fair chance of taking over due to popular support and in the 2nd would aim at the fact that the heir is afraid of being passed over by one of his brothers and thus decides to make a grab for the throne before his father's death.