I've had a few dragons from a young age through adulthood. Each one has had it's own unique developments in color. I've had a couple absolute stunners as babies that simply faded as they went to adulthood and I've had a couple drab looking babies turn into gorgeous adults. There are a few rules that seem to hold--adult color and color comparison WITHIN clutches--but for the most part it seems to be quite a toss-up. I think it's part of what keeps us guessing and makes these animals even more interesting. Here are a couple examples:
Pyro as a baby...showed a deep, intense red/orange color on his entire head and on stripes down his body:

Pyro as a sub adult...his colors have faded. He no longer has much color on his head and the rest of his body is not very vibrant. Still a very cool looking and patterned dragon, just not as colorful:

Pumpkin as a baby. She was mostly brown with orange by her ears and along the fringe of her sides.

Pumpkin as an adult. Picture says it all:





