Kate (Rehmann) Heinecke was born on Saturday, April 7, 1877 in Hammonton, Atlantic County, New Jersey. She was the daughter of Christopher, Sr and Wilhelmina (Wolmelsdorf) Rehmann.

In the 1880 census, she, her parents and siblings were living in Hammonton. The 1900 report gives their address as Eleventh Street in Hammonton.

Circa 1903, she married Edward Ernst Heinecke who was born on December 7, 1877 in New York City.

They had one child, Louise I. (Heinecke) Sowden who was born in 1904.

The 1910 census has Kate and her husband, Edward, living on Front Street in Hammonton with their daughter and a nephew, Edward Reibel. By 1918, they were at 1148 Frankfort Avenue in Philadelphia where they were still living at the time of the 1920 census. At that time, in addition to their daughter, Louise, their niece Bertha P Moore were in the house.

A house at 1312 East Hewson Street in the city was their home in 1930 and 1940. In the latter survey, Kate, her husband and daughter, Louise, were joined in the house by their grandson, Harry Edward Sowden.