Almost everybody in two generations of a family who were previously very easy to find in the records seem to just disappear after the 1911 census, I can't find any records for any of them.
Hiram (1846-1909) and Mary Ann (1848-1900) Greenwood are very easy to find. Their daughter Mary Ellen was born in 1870 in Salford, then they moved out to Charlesworth, Derbyshire where Thomas (1874-1932) was born and married Martha Bennett (1873-1941). They are very easy to find, and all their children are on the 1911 census, Mary Alice born 1899, Ethel born 1902, Lily born 1909 and Frank born 1910. I can't find anything definite about any of these children after the 1911 census. There is a possibility they emigrated to Quebec, Canada, but I could be making a completely false link there.
The younger siblings of Thomas Greenwood also seem to completely disappear from all records. Mary Frances was born in 1876 in Broadbottom, Cheshire. The last record she appears on is the 1891 census as daughter, single, age 15, Jack Frame Tenter Cotton, living at Earnshaw Street, Hollingworth. I remember being told that she worked as a domestic living in servant in that area.
Jane Ann was born in 1879 in Broadbottom, Cheshire, and she too last appears on the records in the 1891 census as daughter, single, age 12, scholar. There is a tiny possibility that she is the same person as a listed marriage with no husband name shown on the record, in Glossop, Derbyshire in July 1899.
The only remote possibility I can find in the records is maybe a connection with people sailing to Quebec, Montreal from Liverpool. There is probably another explanation for all these people being impossible to find in the records. I searched marriages, deaths and censuses and found nothing else.
Hiram's grandmother, Fanny Greenwood born 1801 Heptonstall, had moved with all the family to Salford, where two generations were born, then moved out to Charlesworth after she was widowed, and is listed as a housekeeper in Charlesworth, Derbyshire, on the 1861 census, with her daughter Mary and two grandchildren, both from different children, Henry Greenwood age 7 and Joseph Smith age 2. So there is a strong family link with Charlesworth after that, and a possibility that family members were domestic servants.