You won't know!

While genetics can give you some idea it has not been 100% correct in determining the answers to your questions. While the NERD lemon has one of the best records as far as brighter pastels go it still is not a 100% record. I've actually taken a liking to the blond lines of pastel as they seem to mature with the least amount of browning out. Granted they start being a little darker on the spectrum of pastels to begin with.

These are our 2 year old blond girl. Pictures don't really do her justice though!