I had Nerd from summer of 78 with his brother Ferd. The shop thought they were a couple of years old at that point but no real clue. Pretty sure they were wild caught and had never seen a Maxi Poconos before but pretty sure they were pretty new to the pet trade back then.
Ferd got sick a few years in and Nerd, the sickly, skinny one, with bad feather color soldiered on for 31 years with me and never acted old or frail, he was just Nerd and played, demanded treats, and ran around doing Nerd stuff. He had no clue he was old till he finally got something that we thought at first was just a bad patch till I realized he was truly sick.
The vet and us did the best we could but he was really run down and under weight. He had good and bad days and oxygen helped but he left us a few weeks later close to Xmas 2009
The vet did say she was amazed how old he was and remembered him as a sweetheart even after he bit her on their first meeting.
Almost all of his life he just stayed the same and was a little tank that only got sick a few times to the end and always looked and weighed the same even though he was a skinny little runt, I sure miss him