The twins were born 24 October 1929 according to the informatuon on Nora's naturalization but can only see possibilities for 1928 on the SSDI. The 1930 Census was taken 1 st April 1930 so the age of the twins at 1 year or 1 year 3 months (crossed out) - might mean the birth date was a year earlier that 1929

Social Security Number on one of the possible deaths was issued in New York so might be a good possibility.
Teresa F. McManus. Born 24 th October 1928 and died 2 March 1990
Last Residence: 08757 Toms River, Ocean, New Jersey.
SSN issued: New York (Before 1951)
The 2 possibilities for the other twin - will send by pm incase you wish to investigate those further.
Sandra