Not sure how to describe my family structure, but my mum wears a belt for the most part. I have 2 brothers and a sister. The boys were locked till 18 nd then they went on to college.
The boys do have it easier, but I haven't really discussed this topic with them a lot so I don't know of thier experiences.
This practice is some what common where I live and from what I know my cousins are also belted (until marriage).
My parents use it as a way to prevent pre-marital sex and masturbation. My mum has been in her belt since I remember. I was fitted with mine a bit after my periods but only during the weekends and vacations. Once I got older, especially during COVID it was on me all the time. I went to a school which was very open in nature so there were no concerns of "accidents" to happen.
If I didn't properly satisfy your curiosity, just ask more.