This dragon's name is Eclaire. He is a magically gifted dragon. Allegedly, I might add. You have not seen him conduct any magic under his own will besides maybe moving his wings whenever you're not paying attention to him. He gained his magic from the all-mother, which is a concept in dragon-hood where every dragon can derive the origin of their power to one creature, the all-mother, and that she gave every dragon their powers.
A long time, Eclair and the other 4 dragons at your house moved in. Allegedly, because your house held an extreme power that one of the other dragons were drawn to. This extreme power is the ability to control space. Dragons, apparently, fall into two categories, time-seeking and space-seeking. Space-seekers seek out power sources for space, and time-seekers do the same but for time power. Your dragons are all space seekers, if it wasn't obvious.
Eclaire's parents died in a war fought between some of the time-seekers and space-seekers over who's power distinction was better. Everyone alive today thinks the war was frivolous because there is literally no distinction between time and space because they are both tied together, intertwined to be forever. As a result of his parents dying in the war, Eclaire was forced into an orphanage where he met the other 4 dragons of your house.