For the next step?
If you get someone to look up in Kent 1871 then you may be able to deduce Robert's parents?
Here are all the Parker from Billericay 1861 (RG9):
PARKER ABRAHAM 58 1076 6 BLL
PARKER CHARLES 40 1075 75 SNF
PARKER CHARLES 13 1076 6 BLL
PARKER CHARLOTTE 36 1077 27 DWH
PARKER DANIEL 75 1077 61 WKF
PARKER ELIZABETH 10 1075 107 SNF
PARKER ELIZABETH 10 1076 6 BLL
PARKER EMMA 23 1077 27 DWH
PARKER EMMA 14 1075 75 SNF
PARKER EMMA 3 1075 116 SWD
PARKER ESTHER 5 1075 176 IGV
PARKER GEORGE 37 1075 107 SNF
PARKER GEORGE 2 1075 107 SNF
PARKER GRACE 56 1076 6 BLL
PARKER GRACE 17 1075 42 BRW
PARKER HARRIET 4 1075 107 SNF
PARKER HENRY 55 1076 153 HUT
PARKER HENRY 6 1075 107 SNF
PARKER JANE ELIZABETH 14 1075 107 SNF
PARKER JOHN 56 1076 9 BLL
PARKER MARIA 68 1077 61 WKF
PARKER MARIA 19 1075 220 LWR
PARKER MARY 60 1075 116 SWD
PARKER MARY ANN 37 1075 107 SNF
PARKER MARY ANN 12 1075 107 SNF
PARKER MARY ANN 12 1076 153 HUT
PARKER NATHANIEL 59 1075 107 SNF
PARKER NATHANIEL 22 1075 107 SNF
PARKER NATHANIEL 14 1076 6 BLL
PARKER SAMUEL 62 1075 116 SWD
PARKER SAMUEL 15 1076 153 HUT
PARKER SARAH 53 1076 153 HUT
PARKER SARAH 44 1075 75 SNF
PARKER SARAH 21 1075 86 SNF
PARKER SUSAN 27 1075 116 SWD
PARKER THOMAS 52 1075 104 SNF
PARKER WILLIAM 53 1077 27 DWH
PARKER WILLIAM 50 1075 86 SNF
PARKER WILLIAM 26 1076 6 BLL
1881 census from LDS:
Name Relation Marital Status Gender Age Birthplace Occupation Disability
Robert PARKER Head M Male 47 Billericay, Essex, England Coach Builder
Hannah PARKER Wife M Female 42 Langton Hill, Essex, England
Ellen PARKER Daur U Female 18 Great Bearstow, Essex, England
Fredrick PARKER Son U Male 16 Teston, Kent, England Scholar
Edward PARKER Son U Male 13 Teston, Kent, England Scholar
Warner PARKER Son U Male 11 Teston, Kent, England Scholar
Louisa I. OSBORNE Lodger U Female 67 Sidmouth, Devon, England Formerly Governess
Source Information:
Dwelling 32 Mote Rd
Census Place Maidstone, Kent, England
Family History Library Film 1341222
Public Records Office Reference RG11
Piece / Folio 0930 / 42
Page Number 3
Good hunting,
Geoff.