Unusual family dynamics

My Dad, R. Loyle Borton (b. July 4, 1907), the 6th of 9 children (7 of whom lived into adulthood - such a mortality rate was not uncommon in those days), was just weeks shy of 50 when I was born, eldest of 3 children in his second marriage. Thus I have an older half-brother (Jerry) and half-sister (Joanne), both now deceased, who would be 76 and 74 respectively this coming August. I also have several near-contemporary nephews and nieces, the oldest of whom, Jeff, is only 6 weeks younger than I! When Joanne died in August 2007, and I was at her home following the funeral, I was reminded of our enjoyable visits there when we were children, and the home next door of the family of my Dad's younger brother Von (which has since been turned into a home for senior citizens). When Uncle Von died in April 1974, I remember how shocked and stunned Dad was, telling us, "It just doesn't seem real - Von was the youngest of all of us, and the strongest and most vital."