Hmm, I found some Sousa surnames in my search for my Silva family (finally changed to Selby). They also came from the Azores. I wonder if they were related? Also interesting is how your family kept the Silva name, and my family didn't. I've seen various variations in my lineage (from my original ancestor who immigrated from Portugal, born in 1838) from Silva,Salvey, Silvy, and finally Selby. And it's possible the original was DaSilva based on some of my research.