ROBERT McKENZIE "BERT" COFFMAN JR. was born on April 24, 1875 in New York to Robert and Amelia Coffman. His parents had lived in Philadelphia in the late 1860s and early 1870s. There were three older siblings at home in 1880 as well, May, Gertrude, and Harry. 

The 1878 City Directory reveals that the Coffman family was living at 224 Arch Street. In 1879 his younger brother Richard was born. Another brother, John Coffman, came later. When the 1879 City Directory was compiled, the Coffmans lived at 40 North 5th Street, where they remained through 1894. The 1895 City Directory shows the family at 509 Arch Street. Robert M. Coffman Jr. was at that time working as a stableman at the J.B. Van Sciver & Company furniture factory. The 1896 City Directory shows the family still residing at 509 Arch Street. Robert M. Coffman Sr. had gone into the furniture delivery business, and Robert Jr. was working with his father. By 1897 thehe Coffman family had moved to 34 North 5th Street.

By 1897 Robert M. Coffman Jr. had married Charlotte "Lottie" Camp. A son, Robert 3rd, was born in 1897, and four other children followed by 1910, Elmer, Elaine, Anna, and Alma. He worked for his father into the early 1900s. By 1906 Robert M. Coffman had been appointed to the Camden Fire Department.

When the Census was taken in 1910 Robert M. Coffman Jr. was a driver for the Camden Fire Department in Camden NJ.  The family lived with his parents and siblings at 34 North 5th Street, across the street from Camden Fire headquarters. The family remained there through 1914, when the City Directory for 1914-1915 was compiled. In the late 1910s he was working with Engine Company 5 at 14th and Federal Streets. By September of 1918, when he registered for the draft, Robert M. Coffman Jr. had moved to 541 Fulton Place in North Camden. The family remained at that address through at least April of 1930. Robert M. Coffman Jr. was still with the fire department at that time. During this period another Camden Fire Fighter, Edgar R. Ellender Sr., lived five doors away, at 531 Fulton Place.

Robert Coffman retired from the Fire Department during the 1930s. By 1940 he had left Camden. Robert M. Coffman Jr. eventually moved to Miami, Florida where he passed away on May 5, 1973.