With the major caveat that this isn't something I'd bet on at all unless the show itself was aged up as the series went on or neared its end - which I have seen Disney do with some shows my little siblings used to watch, like when Lab Rats started taking itself a little more seriously and they moved it to Disney XD, which has a slightly older target demographic than Disney Channel proper - do you think it's at all possible that The Lion Guard will kill off a character?
For what it's worth, the show has already acknowledged that death occurs and has implied the deaths of several offscreen characters like Aminifu and Scar's old guard (whom they pretty much say were murdered), not to mention that they've introduced characters who died/will die pretty violently in the films (Mufasa, Scar, Nuka, Zira) and kind of expect the audience to have seen at least the first movie anyway, which has the most violent death scenes in the franchise.
Although I'm not expecting any of the Guard to be offed, perhaps we'll see the death of one of the villains/antagonists in typical Disney over the cliff fashion? Or maybe they'll introduce Sarabi or Sarafina and have them die [presumably peacefully] later in the series run, for the sake of closure, and having Kion actually having to deal with the loss of a family member he knows (which would keep it from repeating the funeral plot point in "Just Can't Wait to be Queen" by making it more personal than Aminifu's death).
Again, unlikely in general, but we never know...
Discuss.