What was the name of Hector's infant son?

Hector’s infant son was named Astyanax.

Astyanax was the child of Hector, Troy’s greatest prince and defender, and Andromache, Hector’s wife. In the Iliad, the baby is also given the name Scamandrius, derived from the Scamander River, but Astyanax is the familiar and canonical answer used for Hector’s son.

The child appears in the famous farewell scene between Hector and Andromache. Astyanax becomes frightened by Hector’s horsehair-plumed helmet, and Hector removes it before lifting his son and praying that the boy will become a greater man than his father.

After Troy falls, Greek leaders fear that Astyanax could grow up to avenge the city. Later versions of the myth therefore describe his death, commonly by being thrown from Troy’s walls. Homer’s Iliad ends before that event, so details of his fate belong to later Trojan War traditions rather than the poem’s closing scenes.