Right off the top, I can think of 2 possibilities:
1) At least one of his parents isn't who you think it is
2) The rex coat is the result of a mutated gene. If a mutation that is survivable can happen, there is at least a chance that it could "un-happen." We see it happen in plants all the time, particularly in variegated varieties; a branch or shoot reverts to the parent pattern (usually plain green).
It would have to be option 2 because at the time I didn't have anything but Rex rabbits in there and both rex were blue eyed, which I believe is also recessive, so unless there is a very determined and talented blue eyed cotton tail out there then his parents are who I think, lol. That's an interesting thing to consider though, I wonder if its more likely because the rex coat is probably fairly new in this line? The blue eye was probably introduced from a normal eyed parent into the Rex until the rex coat was achieved. I have the really nice show line Rex and the play around with colors and stuff Rex which includes the blue eyes. I don't mix the lower quality in with the better examples of the breed. But this sort of thing is probably why it's so hard to develop a new breed in any species. You get throw backs in a lot of generations until the breed is breeding true almost all the time. Interesting tho. Thank you.
I am not a genetics expert like Bunny Lady, but I would think you would continue throwing in recessive traits on down the line as far as you go because of how interesting DNA and chromosomes work out. It's just neat to see traits throw in that one wasn't expecting.
It's very interesting, his coat is different from say a New Zealand or Cali although I can't exactly say why other then most of his guard hairs are very short and he's incredibly soft but he doesn't have that Rex coat. His face hair near his eyes and on his nose almost looks like a bad quality rex, lol. A few of his whiskers are actually crimped like the Rex as well but most are straight. It's too bad he had the normal coat because he has an amazing personality Oh well he'll make a great pet bunny for someone