Yes it is, but the rarest is the RAINBOW DRAGON!!
You get a Sun Dragon
Yes it is very rare
You have to breed a sun and moon dragon together
you need a mommy sun dragon and a daddy sun dragon. and its dragonvale by the way not dragon city urs truly nazir mtoka
the sun dragon can get about a little bit bigger than a fully grown lava dragon
There is a good chance that you will get a evergreen dragon but it is very rare (not impposible) to get a lichen dragon
There is no such thing as a Birthstone Dragon on DragonVale
Most likely a anything with SUN in it
No, they only have to be adults. However, the higher the dragon level, the higher the chances are of getting a rare dragon.
You have to breed one; though it will be very hard.
You would either get a Cactus dragon, a Storm dragon, a Lichen dragon, an Ash dragon, a Hail dragon, a Sun dragon, or a Moon dragon.
As of July 2012, there has not been a star dragon in DragonVale.