Concept for Hyperborea’s Spike. Similarly hatched by Twilight as part of her entrance exam, she and Glados co-raised the young drake until she and Spike were old enough to look after each other. He is distantly related to House Invictus (and by extension, Twilight) by virtue of being a direct descendant of the one of the sisters of Twilight’s paternal grandfather (Cave).
 
Here, he’s shorter than the average foal, but longer in body. His wings are also still too small to be capable of anything more than short bursts of flight. Dragons also mature (mentally) differently from ponies; at eight years of age by the time Twilight comes to Ponyville, he has the mentality of a young adult (albeit with a childish streak), and was able to speak eloquently by the time he was only two.
 
It could be centuries before he grows to full size; however, he won’t end up very large.