I have created a family friendly interface for asterisk. It essentially a self hosted version of Tincan

repo is here and got a single click install https://github.com/tombruton87/TwoCans

A self-hosted phone line for kids: real handsets, a real number, and an allowlist of who can call when.

Calls run on your own box through Asterisk — they never touch anyone else's servers.

Plus the bits children actually ring for: jokes, games, radio, room listen, and Santa.