Is the second-born of the Lion King always destined to be the leader of a Lion Guard?
Basically, is anywhere in the show straight up stated that the Great Kings of the Past ALWAYS choose the second-born as the bearer of the Roar and the leader of the Guard? It's heavily implied that is the case, as both Scar and Kion being second-borns got the Roar and the position af a leader, however I don't think it's ever directly confirmed. And I'm talking about the Kings themselves giving the Roar and not leaders passing it onto the next, as this happens with Kion and Vitani (because she's older than Kovu so second-born rule would not work here). This would make sense as the Lion Guard is all about the tradition and things like male-, lion- and five-only members have existed since the foundation of the Guard itself.
If not, then could there be a possibility of a third-born child getting the position instead of the second-born? Also, what happens if the heir dies? Does the second child (Leader of the Guard) become the heir AND the Leader all at once or does he pass the Lion Guard's duties away to the third-born or some other relative in the family?