Thanks for the info.
Ha ha indeed, the joke is on me. I am sure you will appreciate that this is a bit of a shock as reality appears somewhat different to what I grew up believing. I found out later in life that my dad had been married before and had, what I was told, two sons. I obviously never knew them. I understood that there was some sort of family rift but didn't know what exactly. It's a;; a bit mind blowing!