There are many examples of this, but one that comes immediately to mind is the evolution of my favourite LDAP-enabled music player, airsonic-advanced

Subsonic begat libresonic

Libresonic begat airsonic as well as a whole bunch of other projects.

Airsonic begat airsonic-advanced

Airsonic-advanced begat kagemomiji/airsonic-advanced, however the maintainer of the parent codebase, randomnicode, wants to do the right thing and get their code up to snuff with the opensubsonic API (not sure where that fits in to thr history) so kagemomji can take over.