Jeremiah Cohan was a son of Michael Cohan (Keoghane) and Jane Scott.
Nellie Costigan was a daughter of James Costigan and Mary Burns.

As a young boy Jeremiah worked as a saddle and harness maker before he turned to dancing and acting.

Jeremiah John Cohan (26) of Providence and Helen Frances (Nellie) Costigan (19) of Providence married on 12 September 1874 in Providence, Rhode Island.

Children born @ Providene, Rhode Island

Maude Cohan, 1875- 31 August 1876

Josephine Mary Cohan, 24 December 1876.  She married Frederick Niblo

George Michael Cohan, 3 July 1878, although his family say 4th July was his birth date

Jeremiah Cohan, an accomplished actor and performer.  He, his wife and two living children Josephine and Michael performed as "The Four Cohans" vaudeville act.  Jeremiah was portrayed by Walter Huston in the film "Yankee Doodle Dandy".

From Newspaper:
COHAN’S SILVER WEDDING.

Twenty-Fifth Anniversary of Theatrical Marriage to be Celebrated New Week.
An interesting silver wedding celebration will be that of Mr. and Mrs. Jerry Cohan of the Four Cohans, which is to take place at the New Haven house on Tuesday, September 12, during the engagement of those clever players at PoII's theater next week. On September 12, 1874, Jerry Cohan and Helen Costigan were married at St. Joseph's cathedral, St. Louis, by Rev. Father Bivins. The best man was John Cox, at present the proprietor of the Surf house at Savin Rock, and who was then the agent for Mr. Cohan's show. Mr. Cox is to be one of the guests of honor at the coming celebration.
George Cohan, son of Mr. and Mrs. Cohan, who is the third of the has just come of age and was married on July 20 to Ethel Levy, said to be among the handsomest young women on the stage. The Cohans have another child, Miss Josie Cohan, their daughter, who completes the Cohan quartet. All four will appear at Poll's.

Census 1880:

Census 1900:

Census 1910:

Census 1920:

Burials:
Jeremiah and Nellie are buried in Woodlawn Cemetery, Bronx, Bronx County, New York