Usage: 2 forms in 2 verses
Form Translated As     In Verse(s)
συνεκτραφέντων being brought up LXX.2Chr.10.8
συνεκτραφέντα having been brought up LXX.2Chr.10.10

Liddell-Scott-Jones

συνεκτρέφω (sunektrephō) to bring up together G:V

συνεκτρέφω-τρέφω,

rear up along with or together, τὸ γεννηθὲν κοινῇ μετ᾽ ἐκείνου [Refs 5th c.BC+]; σ. τοὺς παῖδας assist in bringing them up, [Refs 1st c.AD+]:—passive, grow up with, συνεκτρέφωτραφεὶς ἐμοί [Refs 5th c.BC+]