Is Scootaloo related to Applejack ?

In Season 3 / Episode 6: "Sleepless in Ponyville", In the scene, after Rainbow Dash, finishes telling her 2nd Scary Stories, & just before the group turns in for the 2nd night, right after Rarity tells Sweetie Belle: "Don't worry, u'll be safe with me tonight", Scootaloo immediately makes the following statement: "It's not time for bed, is it ?", the only one who reply's to this statement is Applejack, by replying: "Afraid so, Scootaloo." This seems to imply that Applejack truly is & or related to Scootaloo & this is further displayed in Season 4 / Episode 17: "Somepony to Watch Over Me", in the scene where immediately right after Apple Bloom exits her house window, Sweetie Belle & Scootaloo hide to avoid detection from Applejack entering the room while earlier Sweetie Belle & Scootaloo agree to Apple Bloom that they (Sweetie Belle & Scootaloo) will substitute herself sleeping as "Apple Bloom" in her place, while she (Apple Bloom) is away doing Applejack's pie delivery, Scootaloo seems to know something about how Apple Bloom sleeps that, (@ least does not let it show), that Sweetie Belle does not know about when Scootaloo is noticing how Sweetie Belle is starting to fall sleep as "Apple Bloom" by saying: "Sweetie, no, you gotta sleep like Apple Bloom !," & Sweetie Belle replies by saying: "How does she sleep ?", & Scootaloo replies back to Sweetie Belle by saying: "Like she does everything, with sass". All of this, @ least in my mind, seems to lean to the direction that Scootaloo may very well have some relation to Applejack. If u still seem to disagree w/me about all of this, then let me know, by telling me what u think you're opinion is on all of this.

Since when was Scootaloo related to Dash? She just looks up to her. That doesn't mean she's related to her.

What about Pound Cake and Pumpkin Cake?

They are siblings, even though both their parents are earth ponies. Mr.Cake did say how it was possible for the twins to be one pegasus and one unicorn-maybe something about one of his relatives being one and the other, but he was going way too fast for me to understand it, and it still baffles me.