As per the Kings County death certificate number 4467
Gerhard A Haemmerer, age 80, 27 Feb 1925
Film #2047298 (looking for a newspaper obituary)
It is assumed that a daughter Anna, Charlotte, Rose and Christina as well as the wife Catharina Antonette (Bartels) were still around at that time. Charlotte seems to be married to an Anthony Jockel(s) and Christina may have the name Hoagland with daughter Dorothee. Rose married in Oct 1892 at All Saints Church, Brooklyn to a John Gabler Jr.