PENRITH’S premiership legend John Cartwright penned a heartfelt letter to rising star son Jed before the young player lit up the Auckland Nines at the weekend.

Jed Cartwright, 20, was one of the up-and-coming NRL youngsters to have tongues wagging as his Panthers went within a try of securing the Nines title on Sunday.

And his sister Eden revealed on her Twitter account a touching note their father John wrote for Jed in the lead-up to his son’s first major outing with the Panthers.

“I want you to know how proud of you I am, not because you are about to head to New Zealand to represent the Panthers, but because of what you have gone through to get there,” the letter reads.

Round 19

John Cartwright and his son Jed Cartwright. Source: News Corp Australia

“I watched you in pain playing through the teen years. I’m sure you remember the physical abuse, the sledging, the cowards on social media and probably a million things I never got told, all because who your dad was.

“I remember after one particular game, you were speared into the ground head first and then sledged by the whole opposition team and supporters. After that game I almost begged you to find a sport that made you happy.

“You not only stuck with it, you went from not being able to make your school side at 16 to being the captain of the Titans at 19.”

John writes, “You are a loyal, brave, fantastic young man.

“I will be in New Zealand watching and Poppy Merv will be watching over both of us with a tear in our eye.”

From father to son✨ your journey is just starting Jeddy xx pic.twitter.com/Y7jQyvh03Y — Eden Cartwright (@edencartwright1) January 30, 2017

John Cartwright won a premiership with Penrith in 1991, and his father Merv — Jed’s grandfather — helped build the club. His cousin Bryce Cartwright is one of Penrith’s best young stars.

Jed came through the Gold Coast junior system where his father was coaching at the time, before the Panthers came calling with a three-year offer to lure him back “home”.

Despite the club’s glut of talented young forwards, backrower Jed is considered a very real chance of making his NRL debut this year, bolstered by a stellar Nines campaign.