Spike is of course Spine’s father and still serves as the Ambassador to the Dragonlands, but also sometimes for the Changelings when Thorax is very busy and Spike also has the time to spare. When Spine was young, he spent a lot of time away from his dragon father, as it was far safer for the greedy hybrid to be among the Changeling hive rather than the brutes of the Dragonlands. Due to this Spike missed out on a lot of Spine’s growing up and he regrets it a good deal, even though he knows his efforts with the dragons fostered a much more peaceful time. As an adult, Spike is at a halfway point between bipedal and quadrupedal and can move around either way.
Thorax remains the King/Ruler of the Changelings to this day and was the primary caretaker for Spine when he was young. Thorax insisted the young half-blood be with him after hatching and some time after due to the fact that young Changelings - even half bloods - tend to be out of control when it comes to sapping love or energy, not yet having learned self-control, and can be quite dangerous to other non-changelings. Thorax loves his little sooty bug baby and hopes someday he too will go through the Changeling ‘transformation’ that is viewed as a rite of passage in the hive nowadays.
Pharynx remains as the Royal Guard Captain and Defense Tactician for the Changelings and is quite close with his brother and his nephew. As a foal, Pharynx taught Spine how to fight - not that Spine was great at it - and act menacing. Pharynx has a soft spot for Spine, just as he does for his brother, though more so because Spine reminds him of the days when the Changeling hive was feared and fearsome thanks to his possessing many traits akin to pre-transformation Changelings.
Spine is the only son of Thorax and second son of Spike. A strange hybrid of a dragon and a Changeling, he remains indefinitely stuck in his pre-transformation stage, as is common with half-bloods of the Changeling variety. Unlike Pupa, another Changeling half breed, Spine isn’t the least bit bothered by his mixed heritage. In fact, very little bothers Spine outside of being denied the treat of a well loved gemstone. Careless and happy, he can sometimes be rather obnoxious and stubborn in his gluttony and obliviousness. Spine does possess the ability to breathe fire and it is similar to his father’s. Strangely, Spine possesses a cutiemark, despite having no pony blood.