Father: Jason
https://www.rugbyleagueproject.org/players/jason-hetherington/summary.html
Son (already noted): Kobe
https://www.rugbyleagueproject.org/players/kobe-hetherington/summary.html
Other son (twin to Kobe): Zac
https://www.rugbyleagueproject.org/players/zac-hetherington/summary.html
You can use the same birthdate etc as Kobe
Source:
https://www.abc.net.au/news/2016-06-24/rockhamptons-sporting-siblings-follow-in-parents-big-footsteps/7542144
https://www.nine.com.au/sport/nrl/grand-final-news-2025-the-mole-kobe-hetherington-father-jason-brisbane-broncos-vs-storm-exclusive-20251002-p5mzqz.html
https://www.nrl.com/news/2021/05/22/from-the-backyard-to-the-scg-kobe-carries-on-family-tradition/
Updated