Sally Bruckheimer <sallybru@...>
There are a bunch of da Silva Rosa's found in the Amsterdam marriages and a
bigger bunch of Nunes Cardozo's - although none matching your Abraham and
Sarah - so you may have ancestors or cousins in the Amsterdam records.
In the Amsterdam Sephardi records, there are 3 Guidon da Silva
Rosa's(probably your Guideon), likely >from the same family as yours since
this is a rather odd first name for the group.
So check Amsterdam - there was a lot of overlap of the two communities.