Hi, i`m not related, but maybe i can be of some assistance.
I havent found anything on the Seroy or Basca families in Bridgeport before 1905 when they first appear in the city directories exept for Joseph Sr. who died the year before. The Joseph Seroy that is in Bridgeport from 1905 onward is Joseph & Annie`s son, Joseph Henry Seroy, born abt 1882, "at sea" according to the 1920 census.
There is a Conn Death Index record for a Joseph Seroy.Birth Date: abt 1852; Age at Death: 52; Death Date: 30 Jan 1904; Death Place: Connecticut;
Burial Place: Stonington, New London, Connecticut
Cemetery: St. Michael's Cemetery.
You might try to contact the cemetery to see if they have a burial card, and contact St. Micheals Church in Pawcatuck, CT ( Pawcatuck is part of Stonington ) and see if they have any record of the death. Then if any of their records show he died in Stonington, you can obtain a death certificate from the town clerk.
the mother Annie appears in the 1920 & 1930 census in Bridgeport but not in 1940 so she probably died there between 1930 & '40. John Basca & Mary J both died in Bridgeport so i would suggest getting their death certificates from the town clerk.
I`ll do some more looking tomorow to see if there is anything else on them. Let me know if you have more info on the families or if you have any questions.