what colour will these babies be?

Question
I have 3 baby budgies which are approx. 3 weeks old...they are starting to develop some colour...the oldest has some blue around his tail and blue/purple around his neck, the middle has a bit of blue around the tail and the youngest has only yellow splattered around his/her entire body...The mom and dad are yellow/green. I have done some research and found sites on genetics, etc. but I don't have a scientific brain to determine my only question which is:  is it possible for my babies to be blue/purple if the parents are not? I am really hoping that the colour will stay as I really like it. Is it possible that the colour will end up turning green/yellow eventhough it is blue now?
Any feedback would be greatly appreciated.
Thank you.
PS-I find your site very very helpful.

Answer
Hello Agnes! Im glad to hear that you find me very helpful! it makes me glad to know i am helping others so much.
The normal color for a keet is the standard green, with a yellow head complete with bars going all the way down to the mid back, a blue patch on the cheek as well as black spots below the bill, green chest, and a blue tail. As you can see, the keets can come in other colors such as green/yellow pieds, blues and violets. Green is the strongest color and green parents will produce green babies.
EX: blue male + green female= green and green yellow pied chciks (maybe with a hint of blue on the chest.
green male + green/yellow pied female = green and yellow babies.
The only time you will get blue or violet babies are when blues and white/blue pieds breed. But since green is the dominate color, any keet that is green will produce green babies. In a rare case of breeding a say yellow female with a white/blue male might border the line of green. Some may come out all yellow with hints of broken bars, or perhaps a rainbow color. Chances are if the tails are blue then they will be green/ yellow pieds. The other ones with blue around his neck is probably a rainbow mix, a hint of green with some blue making it a teal color. It is possible to have blue babies with green parents. It is rare but not impossible. Thats the best part about breeding, you never know what your gunna get! its always a mystery!