Zack was curious about what life was like for these newly-incontinent girls, and he thought, what better way to find out than to become one himself? He thought about it, and realized that it would be too obvious if he changed but had no memories of living as an incontinent girl, so he decided to alter reality even further.
"There is a disease that causes boys to swiftly turn into girls overnight, and become diaper dependent just like other girls. I caught this disease yesterday and am now a girl, wearing appropriate attire." Zack's body changed as he grew breasts, his hair lengthened, his genitals inverted, and his proportions became more feminine. A bra materialized around her new breasts, and his boxers transformed into a bulky, thickly-padded diaper, the outline clearly visible through her jeans. She was a girl now, just like all the others.
Zack felt an alien sensation as her bladder released without her control or will, making her new vagina leak pee into her diaper. She tried to stop it, to clench her muscles to hold it back, but it was completely futile; in this new reality, girls simply lacked any muscular control over their excretion. It just happened on its own, like a baby. Fortunately, Zack's diaper held back the flood, leaving her with the not-unpleasant sensation of the diaper's warm, moist interior rubbing against her new genitals.
"Mom... I just wet myself," she admitted sheepishly to her mother.
"Well Zack, I'm afraid that's just how it is for us girls. Your diaper should be good for another 3 wets before you have to change it. I know you might not like wearing your waste around with you, but you'll go broke if you change your diaper every time you tinkle. Just be glad we can afford disposeables, when I was your age I had to wear cloth diapers and not only did they leak more often, but I had to wash out my own poop to reuse them later."
Clearly, Zack's changes had rippled through the fabric of history, normalizing diapers for women everywhere. She wondered what to do next...