This comment made me create an account here, that's something. I will try to make my answer short as I can.



That is my story and I am writing it for kids, so it was clear. Spike will play his short but very important role in it. He is where he is not only because of that reason.



I love the picture, kids LOVED the picture when I showed it to them (their parents as well). I treat Spike as a child and I just can't imagine leaving him at Twilight's castle when others are having bonding time. (I hope I expressed that properly.)



I don't know if I am a brony and honestly I don't care if I am one or not. I will repeat myself: this story is for kids I know who like MLP, not bronies who each have their own theory. Oh and one more thing. For some even a dog can be a part of a family, not to mention someone you most probably grow up with...