Had this rough idea for quite a while but didn't know how would I exactly present it. I did want to focus on trying to bring the scale of destruction into another light. Afterall that tree was pretty damn huge and old when you construct it by looking at the interiors. It had to be a significant loss for everyone, simply because of its age and place in history. Not to mention that amount of books that were certainly destroyed.
Of course, realistically a totally leveled tree wouldn't sprout again right in the middle of the trunk, but I took a little bit of freedom so it'd make sense in both artistic side and story viewpoint. I like to think that one day the old overgrown hollow remains of the golden oak would become one with the grown sprout, effectively renewing the tree in its glory.
I kind of regret not putting Spike in there. I just forgot about him after I threw away the idea of having the whole mane six gazing at the sproutling around Twilight.
(EDIT): There's a strange black line around the bottom appearing occasionally.. It's something on Deviantart's side, not being present in the full res picture. The whole site has been laggy as hell recently.