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[MrBredli]

It's a bit hard to get snakes that are 6 months older than another (though not impossible) as they are generally all born at the same time each year. If i were you i would buy a female that is one year older than your male. I would attempt to breed her at 3 or 4 years of age.

Edit: Forgot to mention that the reason for buying an older female is because females generally take a little longer to mature than males do.