My Grandfather was a USAAF Test Pilot, his brother flew B-17s, his other brother 24s. This on my mother's side. On my fathers side, I have two World War Two generation pilots as well. I'm going into military aviation now, with a love for 17s, and a mild fondness for 24s... Oh, and I'm adopted. It wouldn't surprise me if it is genetic. If not, good job conditioning the boys! Keep it up and we'll have new AHers in no time!