so, fun fact: this character was actually first created back in 2016 but first started out as more or less looking like a Lego Duplo toy engine, but after some development, he's become more of a realistic looking steam locomotive. Which is funny because Gary despite his appearance, is not actually based on any steam engine in real life. after arriving on Sodor in 1949 by boat, he was faced with a bunch of problems upon his first day, examples being his small firebox which made traveling at far distances a lot harder, his 0-4-2 wheel configuration combined with his quite long body length, also made traveling at high speeds or exiting out of stations a lot more difficult. The Fat Controller had noticed Gary had been struggling on his first week quite immensely and offered to take him to 'Crew' to fix him up. While tempting, Gary refused the offer because he doesn't see his handicap as a bad thing that needs to he fixed, but rather as a fun challenge for himself as a character because he sees himself as a strong engine who could handle tasks himself.
while overhearing the entire conversation nearby, Gary had reminded Henry of himself on the day of his first crash a couple years back while pulling the Flying Kipper, concerned for Gary and his struggles Henry went to go have a talk with Gary by himself. While the two were talking later that night in Gary's makeshift shed, Henry had told Gary that his situation and struggles, reminded Henry of himself for when he was younger, telling him his odd basis prior to the fix up had restricted him from working properly while working on the branch line, Gary had noticed Henry was concerned for him, but assures him that he shouldn't worry so much about him
while thankful Henry is so concerned for him, he tells him that he doesn't see his off-putting appearance as a bad thing, and that he doesn't mind a good challenge when the opportunity comes up and pushes himself to be the best he can be, not letting his handicap stop him from doing what he loves best, working.
Henry smiled, thanking Gary for assuring him not to worry, but before Henry could leave, Gary tells him one more thing before going. "although, I wouldn't mind the help sometime." as he smiled back.