You know, I actually read this idea in a fanfic … But after knowing that Grogar could or would be the villain in season 9, I started thinking … What if the parents of Applejack are alive? .. many think they are dead, but never confirm anything …. And I have seen this concept many times, (I will only say an example) as in “Hey Arnold” (film 2) where Arnold’s parents are known. ..
 
And also, maybe that’s why they showed us the parents of the little Apples, so we could meet them and then surprise us with something else.
 
Or who knows, as Grogar has the power to “revive the dead” or something like that (I don’t remember very well), I hope that doesn’t happen …
 
I’ll just wait until I see that in the series or at least in a comic and give me an answer … I just hope it does not take too long.