I'm not gonna get into whether you should or shouldn't dye them - thats your prerogative.

However, based on the crystals thing, I do have to comment.... yes, by Halloween they should clear up. but they can reappear over night. Crystals are serious and once a cat develops a propensity towards them, they'll continually get them. Ducky is young to start having them, which leads me to believe he'll have them chronically. From my experience with Pouncer, I do anything in my power to keep him stress free... sometimes I think I stress myself out in order to keep him stress free He just had very expensive surgery so that the crystals won't kill him. He'll forever stress and get crystals but now he'll be able to pass them.

Lastly, a LOT of things that are safe for dogs are horribly toxic to cats. So just because a mom dog can groom her pup without getting sick, doesn't mean a cat won't experience a reaction.

If you really want to dye them, contact your local cat folks (not sure what they're called, but its kinda like the AKC for cats) and ask them what they recommend for color.