Troilus

The Kypria (based on)
The death of Troilus

By the murder or capture of members of Priam's own family the Greeks intended to sap the Trojan ruler's will to resist.
His youngest son Troilus was an especially desirable target for it had been prophesied that Troy would never be taken if Troilus survived to his twentieth year.

The siege forced the Trojans to go outside the walls to draw water from a fountain house in the temple of Thymbrian Apollo. The temple itself was considered to be neutral ground, and both sides worshipped there.

It is said that Achilles had seen Polyxena, daughter of Priam, when she came to worship at the shrine with her mother Hecabe, and had fallen in love with her.

This did not prevent him from setting an ambush for her and her brother when Troilus escorted her to the fountain to fetch water. Both of Priam's children attempted to flee, Polyxena dropping her hydria as she ran. Achilles' famed speed of foot enabled him to outrun and bring down Troilus' horse and Troilus was slain, desecrating the sanctuary.

Neither the god nor the sister ever forgot or forgave; years later, Polyxena lured Achilles into a honey-trap at the same fountain; Apollo was on hand to steady the aim of her brother Paris, and Achilles fell. And when they caught her, the vengeful Greeks cut her throat on the tomb of their fallen hero.