Could be like the anery boa constrictors that "brown out" as they age? I had a nice albino boa that got more and more yellow as she got older, so I think you have a good chance that this is the case.

Not really a huge fan of the snows, but yellow snows sounds pretty nice. Got pics of the parents? Keep me posted man.
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Travis Rose
Lazy S Snake Ranch
3.7 Kenyan sand boas (various morphs)
1.2 Indian sand boas
0.3 Dogs
0.1 Cat
X.X Fish
0.1 Very understanding wife
2.0 Future Snake Lovers