I need to have multiple repo's that have a common ancestor. The ancestor will be changed from time to time to correct bugs or add functionality. Each sub repo will be connected to GitHub and will be public. The sub repo's will have completely different functionality. The master will have common functionality the subs will need. The master repo will be private.
I saw tree structures — that I think can basically connect two repos, but I'm not sure if that's the correct solution or how to implement.
I have not tried anything.