Talk:Spike/@comment-68.160.246.12-20120515102200

Here's what I think. Celestia took to the initial raising of Spike, given the general lack of pony knowledge on dragon raising, only giving him to Twilight as an assistant when both were mature enough for it. Hence, the Twi/Spike relationship - prior to being sent off to Ponyville - would be more formal, and becoming more sibling as they both learned to adjust to Ponyville. This would also be consistent that leaving Shining (whom she still probably saw every day while at Canterlot), her relationship with Spike would be upgraded to the sibling nature to make up for not being around Shining.