I hope you still get this message as have only just found your post which is over 6 years old. I believe that John Campbell is part of my family tree. Do you have anymore information about him? My grandfather was Charles Campbell (my great grandfather another Charles Campbell) who I believe is John's father. I know he went to Argentina. I have some notes from a family member at home which also mentions a relative having gone to the US and became a military man possibly a colonel but will have to check my notes. I will come back to you on this but in the meantime if you can share any information that would be great.