I'll share mine, not as long or exciting, but one which inspired me to ask for a train set for Christmas that year!
My grandfather worked the railway from the 70s to the late 90s, he helped to pull up the line from Dublin-Navan in '06/'09 (greatest mistake he would often mumble, even into his twilight years with dementia. Through his connections still within the network, he got us on a working to Platin Cement Drogheda in the cab of an engine, now, young me was unable to take in all the details, but i remember gawking up at this giant, awe inspiring orange machine, caked in the oil and grease only an Irish locomotive can apparently accrue, and i distinctly remember believing this engine was black. Pointing the black engine out to my grandfather got a chuckle, and he corrected me, "This one, is in fact Orange, the days of black engines are long done and dusted". I remember being lifted into the cab of this engine, and being amazed at the complexity of the engine, and how one man could figure it all out! but i was shown the most important piece of equipment. without which, this train could not function, and the piece that i would be in charge of, The horn! and let me tell you, i mastered that horn! that engine was probably sent to Inichore to get the horn refurbished after i was done! But it was an amazing experience, one I'm proud to have had. And i remember walking through the yard with no hi-vis on any of us, Im not sure that would fly anymore, so i feel very lucky and privileged to have had the experience i had! My poor mother spend an age chasing us in the car!
Another one is the sleeper incident. and lets just say, most of my grandfathers sheds are built from IE sleeper and rail from Irish Rail, triggering an investigation as to why there was a tow truck laden down with sleepers leaving a yard. (not into my grandfather, but into the purported seller of said sleepers mind you). We're still getting great use out of those sleepers!