I Am Searching for Information About Joseph Simmons and His Father Frederick Simmons

Joseph Simmons was my great grandfather. He was married at Poplar in Middlesex England in 1881. He was a Mariner at the time. Not sure how he came to Australia, but next appears at Williamstown in Victoria as a Fireman Stevedore in 1914. Joseph is obviously Mulato, as evidenced in a later photograph with his wife and children. This colouration has continued down through some of the family.

Frederick Simmons, a Master Mariner. was my great great grandfather and my only info on him is on Joseph's Marriage Certificate. No other info on him has been found despite considerable search attempts by various family members over the last 30 years.
Any help or suggestions where to look would be would appreciated.