Just . . . wow. My soft spot for dragons might be messing with my judgement here, but really, who wouldn't want a dragon as their friend? The only concern I have is that, once the dragonlings are a bit older, they become formidable companions. It's a lot of power to grant an adventuring party, especially early in their careers.
Some ways to offset this:
General prejudice of the population against the dragon-friends. They might have a hard time finding work after this.
Weapons with anti-dragon powers now work equally well against PCs.
Perhaps only allow one or two dragonlings to survive, to be cared for by the whole party rather than by each member. If the party ever splits, expect custody disputes to ensue.
These are rather small nitpicks to an otherwise excellent submission. Have an HoH!