Aww... It's a cute baby dragon. It has a large, shield-like object at the end of its tail that it uses for protection.
And look! It's grown its wings! It must be close to maturing.

Young dragons are relatively defenseless. Their scales don't grow in until right before they mature, and they have almost no strength. Once a hatchling's wings grow in, it marks the beginning of maturation. At this point they are usually left alone by their mother and begin to hunt and survive on their own.

Cousin Dumdum claims he's a cousin of Baka I.  Nobody really knows why.  Anyways, Cousin Dumdum is an annoying little mascot, shoving his name after Baka I's in some cases.  Since Baka I is so mild-mannered he doesn't seem to mind, but other dragons scold Dumdum for being such a dumdum.  He's not very well-liked because of his dumdummy qualities such as shouting messages into your head, jumping around and generally being an annoying little sidekick to an otherwise pleasant dragon.