8 year old boy unknowingly being force-femmed by their sibs; the puberty blockers hidden in their food keeping them on the small side, and a flat chastity cage on their 'clitty' locked in place by a paid off bully in the school locker room.
Their tight hole getting trained during drugged sleep on the weekends, carried off from their zonked out place on the couch; plugged up snugly before they're dressed in their pjs, tight girl-print goodnites helping keep everything in.
The silicone eased back out by whatever sib wakes up first, occasionally also using the padding if the morning need to pee is high enough.