Brian To'o describes the relationship as "brothers by choice", a bond that will not be broken by Stephen Crichton's impending move to Canterbury.
Close friends through football and church, To'o and Crichton both made their debut for Penrith in 2019, but their fraternal link long outdates that.
The pair are well aware Friday's preliminary final against Melbourne will be their last together at Penrith if they are beaten.
"We're not brothers by blood, but we are brothers by choice," To'o said.
"If I don't see him for three months, we can catch up one day and it's like we've never been apart.
"We've been in the system together for a very long time, and even off field he's like a brother to me and someone that I look up to.
"To see him earn the rewards for his family by setting himself up for the next few years is great, but it does make me emotional because we've achieved a lot together."
Crichton lists leaving Penrith as one of the hardest decisions he has had to make in life.
And the hardest part of it? Telling To'o.
"Bizza was the first person I told. Him and his partner were pretty emotional," Crichton said.
"I grew up with them and he's been my best mate ever since footy started. It was pretty sad telling him.
"We're heaps tight. The bond that we've had and success that we've had just brought us together."
For Crichton, the reality has now set in that his days with the Panthers are coming to an end.
A Penrith junior, his and Spencer Leniu's looming exits mark the first home-grown local talents to be lured elsewhere during the club's current run of dominance.
Crichton has remained adamant this week he has no regrets over his impending move to Canterbury, while also standing by under-fire Bulldogs coach Cameron Ciraldo.
But the two-time premiership winner said he had also spent the past fortnight thinking about the reality that he had a maximum of two games left for the Panthers.
And most importantly, he is determined to win another premiership with them before he goes.
"I reflect on where I could be, where I would be (without this club)," Crichton said.
"It has (sunk in) now. I really thought about it over the past couple of weeks coming into my last home game last week in this jersey.
"It's probably the hardest thing I've done, but with the opportunity that we have (to end the season with a premiership), it's the best way I can give back to the club."
