Around age five, I was reintroduced to diapers by one of my step-sisters. My birth parents divorced when I was two, and my father wasted no time dating and remarrying... over and over. By the time I was ten years old, I had lost count of the number of step-siblings (and almost step-siblings) I'd had. At the time of my first experiences with diapers, my father was married to a woman with three daughters, one of whom was my age. I can't remember why we started doing it, but she and I would take these baby-doll diapers into the attic and pee in them. The memory is pretty fuzzy, but I remember us going into separate corners of the attic, pulling our pants down, and soaking these little diapers. And I definitely remember that it was her idea.
Shortly after that, I found a baby diaper while digging through the closet (at my mom's), and promptly took it to my mother, requesting to be diapered. She denied my request.
When I was around nine, I deliberately had an "accident" while at my dad's house. I don't remember my exact motives, but I think I was trying to get diapered by my dad, and I already enjoyed peeing in my pants by that point. Feeling adventurous, I waited until my bladder was pretty full, and then stood in front of the toilet and let loose... into my underwear. When I had finished, I concocted a clever plan to "hide" my wet underwear: I was going to take them off and toss them into the corner, and then leave. I felt very accomplished until my father confronted me not long after, asking if I'd had an accident. And again, no diapers.
At the time of the underwear wetting, my father was married to a different woman, who also had three children (two boys, one girl). Her oldest boy was a year younger than me, and he began to have bedwetting issues around that time. He eventually had to start wearing Goodnites to bed, and my passion for diapers was reignited. Every now and then, I'd sneak one from his dresser and take it into the bathroom to pee in it. I'd even wear them around the house sometimes (hidden under my clothes, of course), and once I tried to wear one out to the bowling alley. Unfortunately, my step-brother ratted me out to my dad, and I had to take it off before we left.
I also have a few hazy memories of wetting my pants when people surprised/spooked me, and some times that I grabbed a diaper or two when the opportunity arose (baby diapers in grandma's garage, baby diapers in a nursery, great-aunt's Depends pull-ups, etc). Ever since those first experiences in the attic, my passion for diapers (and wetting in general) has only grown, though I wouldn't say I truly acknowledged it until my teens.