My nan was born 1954 in Ealing to James McMahon and Rose Jennings (but used Saunders from first marriage). My nans brother was born 1951 in Ealing too. I can find James and Rose on electoral rolls in Acton from 1949 to 1957. Rose went by Rose McMahon from 1952, but I'm not sure they never actually married due to not being able to find any evidence anywhere.
I know my great nans (Rose) history and her family from her first marriage. But my nan never knew her biological dad (James) so she has 0 information on him. She actually only knew him by Jerry and that he was Irish, I only found out his birth name from ordering my nans birth certificate, which also has his profession down as an electroplater.
My question is, how do I find out about James before and after he was with Rose? As I only have him on electoral rolls, I'm not even sure I can, but I am fairly new to this!