John Prosser 
Born: Q1 1850 in Merthyr Tydfil District, Glamorgan, Wales (26 409)John's Family
Spouse: Emma Phelps married Q2 1872 in Merthyr Tydfil District, England, Glamorgan
Children: Llewellyn Prosser, Griffith Prosser, Tabitha Prosser, David Prosser
John's Heritage
Parents: John Prosser, Tabitha Llewelyn
Siblings: William Prosser, David Prosser
1911 Census 45 Hillside Terrace, Wattstown, Ynishir, Rhondda, Glamorgan
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 62 | Merthyr, Glamorgan | Coal Miner Hewer | 559 |
| Emma Prosser | Wife | 60 | Cwmbach, Glamorgan | 843 | |
| Llewellyn Prosser | Son | 35 | Cwmbach, Glamorgan | Coal Miner Hewer | 844 |
| David Prosser | Son | 18 | Cwmbach, Glamorgan | Coal Miner Hewer | 847 |
| Beatrice May Prosser | GDaur | 5 | Ystrad, Glamorgan | Coal Miner Hewer |
1901 Census 16 Big Row, Aberdare, Merthyr Tydfil, Glamorgan
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 51 | Merthyr Tydfil | Coal Miner | 559 |
| Emma Prosser | Wife | 48 | Aberdare | 843 | |
| Llewellyn Prosser | Son | 24 | Aberdare | Coal Miner | 844 |
| Griffith John Prosser | Son | 14 | Aberdare | 845 | |
| Tabitha Prosser | Daur | 13 | Aberdare | 846 | |
| David Prosser | Son | 8 | Aberdare | 847 |
1891 Census 17 Big Row, Cefnpennar, Aberdare
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 41 | Aberdare | Coal Miner | 559 |
| Emma Prosser | Wife | 40 | Aberdare | 843 | |
| Llewellyn Prosser | Son | 14 | Aberdare | Coal Miner | 844 |
| Griffith John Prosser | Son | 4 | Aberdare | 845 | |
| Tabitha Prosser | Daur | 3 | Aberdare | 846 | |
| David Hughes | Boarder | 21 | Aberdare | Coal Miner |
1881 Census Glenview Cottage, Llanwonno, Glamorgan, Wales
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 31 | Merthyr Tydfil | Coal Miner | 559 |
| Emma Prosser | Wife | 30 | Aberdare | 843 | |
| Llewellyn Prosser | Son | 4 | Aberdare | Coal Miner | 844 |
1871 Census Crown Row, Aberdare, Merthyr Tydfil, Glamorgan
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 57 | Glamorgan | Coalminer | 556 |
| John Prosser | Son | 21 | Glamorgan | Coal Miner | 559 |
| Llewelyn Prosser | Son | 11 | Glamorgan | Scholar | |
| Ann Prosser | Daur | 24 | Glamorgan | Servant | |
| Ebenezer Prosser | Son | 19 | Glamorgan | Scholar | 1681 |
Checking the records, I can't find any links between Llewelyn Prosser or Ann Prosser and John Prosser. Their mother's maiden names were Davies and Thomas respectively.
1861 Census Tyrffounder, Aberdare, Merthyr Tydfil, Glamorgan
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 45 | Brecon, Brecknockshire | Coalminer | 556 |
| Mary Prosser | Wife | 42 | Merthyr Tydfil, Glamorgan | Coal Miners Wife | 554 |
| William Prosser | Son | 17 | Merthyr Tydfil, Glamorgan | Coal Miner | 557 |
| David Prosser | Son | 15 | Merthyr Tydfil, Glamorgan | Coal Miner | 558 |
| John Prosser | Son | 13 | Merthyr Tydfil, Glamorgan | Coal Miner | 559 |
| Ebenezer Prosser | Son | 11 | Merthyr Tydfil, Glamorgan | Coal Miner | 1681 |
| Morgan Roberts | StepSon | 19 | Merthyr Tydfil, Glamorgan | Coal Miner | |
| John Roberts | StepSon | 17 | Merthyr Tydfil, Glamorgan | Coal Miner | |
| Mary Ann Roberts | StepDaur | 15 | Merthyr Tydfil, Glamorgan | Coal Miners Daughter | |
| Philip Roberts | StepSon | 13 | Merthyr Tydfil, Glamorgan | Coal Miner | |
| David Roberts | StepSon | 11 | Merthyr Tydfil, Glamorgan | Coal Miner | |
| David Roberts | Serv | 18 | Llangendeirne, Carmarthen | House Servant |
1851 CENSUS ABERCANAID DISTRICT. REF.HO.107/2458, ED.6. Piece: 2458 Folio: 207 Schedule: 240
| Name | Position | Age | Where Born | Occupation | BK No |
| John Prosser | Head | 34 | Bre Llanthony | Coalminer | 556 |
| Tabitha Prosser | Wife | 30 | GLA Merthyr Tydfil | 554 | |
| William Prosser | Son | 7 | GLA Merthyr Tydfil | 557 | |
| David Prosser | Son | 3 | GLA Merthyr Tydfil | 558 | |
| John Prosser | Son | 1 | GLA Merthyr Tydfil | 559 |