I used the city directories to determine that Edward's father was Solomon Wilhelm.He appears in the earliest city directory (1873-74) as a freight agent, F. $ P. M. R. R., res w s Saginaw, bet 6th and 7th. In 1880 he's listed as a truckman, res 908 5th. In 1884 he resides at 703 Johnson and has his own transfer line, Wilmelm and Co. In 1900 the transfer line is now Solomon and Sons--Elmer E., Frank W and Edward).Edward is also listed separately as an asst city engr, City Hall, bds 703 N. Johnson. In 1910 Edward is listed as a lumber inspr, still living at 703 N. Johnson. I found only one listing for Pearl G. Darling, student, living at 1801 Trumbull.I determined her father as James E. Darling, who was the city engineer for Bay City!! Hope this helps you in your research.