Hi,
I recently have been researching my Mothers Grandfather "Sidney Aufholz". His brother is the Leopold you are looking for. You need to go into Mundia.com It is free and there is a woman that has done your wives family tree (Here name is Angela). Leopold was her grandfather and changed his name to Attwood or Onwood from Aufholz. This woman has worked very hard on the Aufholz family tree to no avail. Its almost like the name came out of nowhere and every reference to the name is related on the family tree. Leopold & Sidney had many siblings and their father was Julius Auhfholz married to Sarah Rothschild. I am still digging in to find out more on the family. Sidney (my great grandfather) came over to the US around 1905 when his wife Florence was pregnant w/my grandmother. I am not aware of when or if any of the siblings came over to the US.. The Aufholz's came to Islington, UK from Offenbach, Germany. Hope this helps you on your quest! Say HI to your wife, we are distant relatives ;-) We hale from Indiana (but I now live in Oregon). Lisa ;-)