In this case the daughter still has only a 50% chance of being colour defective. Blue colour blindness is far less common, being present in just 5% of all colour blindness sufferers. The genes affected are equal in both sexes.
The cheapest days to fly are usually Tuesday, Wednesday and Saturday. While your information may be only anecdotal evidence, it probably confirms what FareCompare.com's careful study of airline supply and demand confirmed in a 2011 study of U.S. carriers.
The cheapest airfare is usually found in the lowest tourist periods of the year, running from November 1 to December 14 and December 24 to March 31. Prices of flights to Italy can fluctuate dramatically, and while the occasional lucky traveler finds a heavily discounted flight a week before departure, this is rare.