how soon can you tell sex?

got a question, Ive got three plants goin, all in the same pot. The first two are close to ten months old, one is budding beautifully and the other is struggling (Ive got a thread in the Plant Problems about my struggling plant - I need to save the plant) .
Now the third plant is NO MORE than two months old, I figured I wanted to keep a steady flow of smoke. Well I have all three of them in the same pot and under the same lights, and unfortunately for the baby its under a 12/12 light cycle (there the only lights I have at the moment sufficient enough to grow), the amazing thing is its starting to show its a female! its only two inches tall and I already see the white hairs! can plants show sexes that early?

Yup. If your plant is 10 months old and still isn't finished she is one stunted girl! I had one that vegged for about 4 months, was in a small pot and only grew to about 4" tall, looked terrible but was a blueberry so I wanted to try and keep her going. I only have one ballast for my light system and I wanted to flip my plants. I thought "well wtf..." and decided to throw in "lil girl" too. I transplanted it into a 2 gal grow bag like the others and found that she was rootbound like crazy. She had spent all that time growing roots instead of above ground. As soon as I got her in the bigger bag she doubled her size within a week. I didn't feel like I had anything to lose so I threw her into the cabinet with the rest of the plants for 12/12. Son of a gun if it didn't turn out to be a female. Here are a couple of pix of her.

...goddamn.

wont matter how old,if it`s on 12/12 it will flower