There is no such thing as a Birthstone Dragon on DragonVale
As of July 2012, there has not been a star dragon in DragonVale.
You don't breed a Kairos Dragon in DragonVale. You have to get parts to complete it.
To date, there is no grass dragon in DragonVale. You may be thinking of the plant dragon. See the related question.
The incubation time for a rainbow dragon in DragonVale is 48 hours.
Brass Dragon and Fire Dragon
love dragon and panlong dragon
Sonic Dragon and Flower Dragon
Water dragon.
Fire Dragon and Lightning Dragon
Earth Dragon and Cold Dragon
Another dragon