I am a real amateur but had to contribute my small piece of history to the chain. My dad was Albert Walter Gammage from West Haddon, Nr. Rugby, Northants, he was born in 1913 his mother was Fanny (nee Clarke). He had one brother, George and four step brothers and sisters. His father (also lived in West Haddon), Albert Gammage (killed in the first world war). I did read that Godfroi De Gammage came over to England with William the Conqueror, but whether we are actually related to him is probably very unlikely. I hope to go into this in more detail when I retire.
Best wishes to all Gammages in their search.