My wife is a Sonne. Her grandfather was Hans Christian Sonne 1864 - 1943 was born in Bornholm and moved to Warren, PA in the US in 1883 and died in Titusville, PA. His father was Herman Mathias Sonne 1836 - 1886 in Bornholm. He was married to Nicoline Marie Georgene Thorkildsen, daughter of Jens Peter Thorkildsen.
We're visiting Bornholm from June 7 to 9. Any help or suggestions on genealogy research would be appreciated.