Jacquero was a man  enslaved at  Sylvester Manor in Shelter Island.

Per Nathaniel Sylvester’s 1680 last will and testament, Jacquero and his wife, Hannah were owned by his wife Grizzell Sylvester having brought them with her into the marriage.

Jacquero and Hannah had two daughters, Hope and Isabell, who remained enslaved throughout their lives.   Hope was bequeathed to Grizzel Sylvester, and Isabel was bequeathed to her daughter Elizabeth Sylvester.  Because Elizabeth lived in Southampton, this probably meant that Isabel was separated from her family unless Elizabeth was visiting Shelter Island.

Additional reading is available at Sylvester Manor : https://www.sylvestermanor.org/slavery-at-the-manor/hannah-jacquero-hope-isabell/

More research is necessary.