1871 Census Redall Hill, Rowley Regis Harriet Holloway, head, w, 43, Grocer, West Bromwich Mary J, daur, 9, Rowley Regis. Frances Perry, w, 78, Not Known
Possible Harriets sons 1871 137, Green Lane, Arthur Simcox, head, 43, Engineer, West Bromwich Sushanna, wife, 36, Dressmaker, Bloxwich Harriet, sister, 18, Dressmaker, Bloxwich Arthur Holloway, nephew, 13, Cradley Heath Joseph, nephew, 12, Cradley Heath
1861 Census Spinners End, Rowley Regis Henry Holloway, head, 52, Nail Maker, Saltwells, Worcestershire Harriet, wife, 33, West Bromwich Thomas, son, 21, Warehouse Man, Dudley Wood, Worcestershire Arthur, son, 3, Rowley Regis Phillip J , son, 2, Rowley Regis Patience Thompson, serv, 16, House Serv, Gornal
Possible Harriet?? 1851 Census Sweet Turf, Dudley Edward Baker, head, 33, Wollen Draper and Tailor emplying 7 men, Ketley(?)Salop Ann, wife, 38, Bradley Ann Thomings, mother in law, 66, formerly grocer, Birmingham Harriet Simcox, serv, 23, house servant, West Bromwich
Possible 1851 Census?? Brickhills, Walsall, Joseph Simcox, head, 50, Engine Worker, Wednesbury Martha, wife, 53, Wednesbury Arthur, son, 23, Coal Miner, Wednesbury Joseph Javens, lodger, 50, Carpenter, Kingswinfor Thomas Gripton(?), lodger, Lab Boat Loader, Derrington
Possible 1841 ?? Joseph Simcox, 45, Engineer Martha, 45, Arthur, 15, Engineer Joseph, 10 York, 2 Joseph Jeavons, 40, Carpenter John Williams, 35, Engineer
Possible 1841?? Clay Potts Lane, West Bromwich Samuel Simcox, 53, Lab, Ann, 52, William, 25 Samuel, 16, Catherine, 22, Mary, 19, Harriet, 14 Ann, 12
So this looks like the family father and brother Arthur the arthur whose house Arthur Holloway is in in 1871
Possible Harriets sons 1871 137, Green Lane, Arthur Simcox, head, 43, Engineer, West Bromwich Sushanna, wife, 36, Dressmaker, Bloxwich Harriet, sister, 18, Dressmaker, Bloxwich Arthur Holloway, nephew, 13, Cradley Heath Joseph, nephew, 12, Cradley Heath
Possible 1841 ?? Joseph Simcox, 45, Engineer Martha, 45, Arthur, 15, Engineer Joseph, 10 York, 2 Joseph Jeavons, 40, Carpenter John Williams, 35, Engineer
Possible 1851 Census?? Brickhills, Walsall, Joseph Simcox, head, 50, Engine Worker, Wednesbury Martha, wife, 53, Wednesbury Arthur, son, 23, Coal Miner, Wednesbury Joseph Javens, lodger, 50, Carpenter, Kingswinfor Thomas Gripton(?), lodger, Lab Boat Loader, Derrington
Louisa and Harriet Powell are possibly daughters of William and Mary Powell, baptised in Walsall (IGI extracted) and it could be the same Harriet but I can't tie it all together.
"The present is the key to the past" - Charles Lyell