Been a fan of real-life trains since I was two (according to my parents). My late grandmother used to tell me how when she drove me around (back when I was between 2 and 5), every time we stopped at a crossing when a Southern Pacific freight was passing by, I would get super excited and wave to the train. I was a huge fan of Thomas the Tank engine as well (owned the original book collection by the author and used to watch Shining Time Station whenever it aired on PBS when I was young).
I have been fortunate enough to visit the great California State Railroad Museum three times in my life, and I highly recommend it to anyone who is a fan of trains. They have a great collection of locomotives, from old-time steamers to the massive Southern Pacific #4294 AC-12 4-8-8-4 Cab Forward locomotive and some SP, ATSF, WP, and Amtrak diesel power as well.
My grandmother once drove me into town in the late spring/early summer of 2007 (?) when Union Pacific #844 was supposed to make a short stop in town. Unfortunately, it was running late, and instead of stopping in town it just thundered past trying to make up for lost time. It was pretty awesome watching that locomotive rumble past at speed, and the whistle was hauntingly fantastic each and every time the engineer used it.
Every now and then, when I get the chance, I go rail-fanning in Chico and Durham, taking photos of the Union Pacific freights that make their way through our area on the old Southern Pacific tracks. Perhaps one day I will go to Oroville and try to get photos of the old Western Pacific yard that the UP now uses for switching. Shame that the old roundhouse burnt down (you can still see the rough outline of the roundhouse and turntable area on Google Earth).
As for model trains, I got my first HO set (Life-Like Santa Fe freight set, the one with the GP unit) when I turned seven (1997). My dad made a small layout for me on a 4x8 table and until the summer of 1999, I had it in my room running my original trains along with other additions my grandmother had purchased. The old HO layout was removed later that year (before Christmas) and put away.
As for O gauge trains, my grandmother got me my 1st Lionel train set (2001 Santa Fe 4-6-4 O27 set with box car, log car, horse car, and lighted caboose) for Christmas when I was eleven. My dad put together a 5x10 layout for me to run it on. Until the fall of 2005, it sat in the garage, with me using it from time to time. Sadly, my interest in model railroading got lost among the video gaming, sports, and other things that I got interested in, and I began to neglect (not use) the layout. Father finally tore it down in the summer of 2006 to make room for storing stuff. Stored my trains away and in 2013 I started getting back in model railroading (planning new layout and pooling together funds to expand my locomotive/rolling stock roster).
TL;DR: I have loved real-life trains since I was two years of age and model trains since my first HO set when I was seven. Got into O Gauge when I was eleven. I rail-fan from time to time and take photos of UP freights rolling through town on old SP tracks.