https://a860-historicalvitalrecords.nyc.gov/digital-vital-records
I looked at what has been digitalized and found these.
Patrick Agen age 2 in 1865, no cemetery named. John Agen, age 2, 1868, buried in Flatbush Cemetery.
Mary Agan, d 1872, buried in Calvary. William Agan, 1874, Calvary. Elizabeth Agan, 1874, Calvary.
no Eagans buried in Manhattan 1855 to 1875.
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It's always possible she was Catholic and married Wm Park in the Episcopal Church anyway.