Congratulations... Now hang onto them and raise them up into breeders. Or sell them to me 
>>I have been incubating these little guys for over 3.5 months.
That sounds like a good amount of time. Longer incubation periods typically lead to higher hatch rates with this genus.
>>One is a strange colour, the mother was a silver, do you think it could be a silver as well?
Still hard to say. Green imports are know for producing both silver and green offspring with no apparent blending. This is the first time I've heard of a silver female producing greens, although it's long been suspected that will happen.
My best guess is that this specimen will grow into a typical silver specimen or perhaps one of the high orange specimens like one of my females.
It probably also depends on the sex. Males and females of the silver type tend to look quite different (based on relatively small sample size, to be fair).
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Current snakes:
0.2 Gonyosoma oxycephala - (Silver/Yellow)
3.3 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)
3.3 Gonyosoma janseni - (Black & Tan)