These message boards are for help with researching family trees and maybe finding "cousins". This is done with using documents to prove family connections like birth. marriage and death certificates, obituaries, school, military and newspaper accounts. There are many like myself who enjoy helping other with their research or "breaking down a brickwall".
If you want to contact the "living" DeCavalcante family then look for them in social media sites as well as Public Records sites and make contact that way. The odds of any family member seeing any message on this board is very slim. You could look to see if any family trees have been posted and contact the person who submitted that tree.
Also instead of "I think the spelling is correct" for your grandmother's maiden name, look for the records that will give you the right spelling. Her and Sam's Marriage Certificate, your father's birth or death certificate. Also his SSA application for a SSN will have it, but it is my understanding you may need to provide proof your father is deceased to have parents names not be blacked out. You can ask the SSA when you make a FOIA request for the application. Your father's marriage certificate may also have his mother's maiden name. As should you grandmother's death certificate as well as her SSA application if she had a SSN. Could be the reason, if on the slim chance a Decavalcante "cousin" did see your message, but has a different enough spelling of Mary's maiden name as to think you are not connected to their branch of the family.
Good Luck
If you want to contact the "living" DeCavalcante family then look for them in social media sites as well as Public Records sites and make contact that way. The odds of any family member seeing any message on this board is very slim. You could look to see if any family trees have been posted and contact the person who submitted that tree.
Also instead of "I think the spelling is correct" for your grandmother's maiden name, look for the records that will give you the right spelling. Her and Sam's Marriage Certificate, your father's birth or death certificate. Also his SSA application for a SSN will have it, but it is my understanding you may need to provide proof your father is deceased to have parents names not be blacked out. You can ask the SSA when you make a FOIA request for the application. Your father's marriage certificate may also have his mother's maiden name. As should you grandmother's death certificate as well as her SSA application if she had a SSN. Could be the reason, if on the slim chance a Decavalcante "cousin" did see your message, but has a different enough spelling of Mary's maiden name as to think you are not connected to their branch of the family.
Good Luck