I have never experienced a Cavaliers coat to change texture after being neutered (regardless of age), but I have had two bitches whose coat changed colour after they were spayed - I had a blen whose ears lightened and by the time she went over the bridge they were looking pretty white. My current tri bitch has had some colour change on her back/base of tail area - she used to be a very jet black and after her spay this area turned more brownish that totally black.
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