You do not state where Richard and Jemmima are from Is this your Richard:

England, Norfolk Bishop's Transcripts
Name Richard Burgess Sayer
Event Type Christening
Event Date 17 Aug 1817
Event Place Norfolk, England
Gender Male
Father's Name Richard Sayer (occ Butcher)
Mother's Name Sarah



New Zealand, Archives New Zealand, Passenger Lists
Name Richd Burgess Sayer
Event Type Immigration
Event Date 1839
Event Place New Zealand, New Zealand
Age 21
Marital Status Single
Occupation bricklayer
Birth Year (Estimated) 1818
Ship Name Oriental
Departure Port Deal
Departure Date 1839
Arrival Port New Zealand
Arrival Place Deal

Yes, that's the Richard Sayer I'm descended from. I'm seeking details of his forebears and siblings if any.

Poss marriage of parents:

Name Richard Sayer
Spouse's Name Sarah Glasscock
Event Date 04 Jun 1802
Event Place Mundford, Norfolk, England
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This might be your Jemima

England Births and Christenings
Name Jemima Oxenham
Gender Female
Christening Date 25 Jun 1837
Christening Place SAINT MARYS,PORTSEA,HAMPSHIRE,ENGLAND
Birth Date 03 Oct 1826
Father's Name John Oxenham
Mother's Name Elizabeth

There was also a John 1810 and Sarah Baptised in PORTSEA,HAMPSHIRE,ENGLAND to a John and Elizabeth Oxenham

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** this might be your Jemima arriving with her Brother and sister ??

John D?Ly Oxenham Immigration 1839 New Zealand, New Zealand29 Single Shipwright b 1810 Aurora Deal Arrived 1839 New Zealand

Sarah Oxenham Immigration 1839 New Zealand, New Zealand 19 Single Sempstress 1820 Aurora Deal Arrived 1839 New Zealand Deal

Jemima Oxenham** Immigration 1839 New Zealand, New Zealand 15 Single Sempstress 1824 Aurora Deal Arrived 1839 New Zealand

Yes, this is Jemima, Sarah and John arriving in NZ. I am seeking info on their forebears too.

Poss marriage of Jemima's parents
Name John Oxenham
Spouse's Name Elizabeth Norman
Event Date 27 Jul 1807
Event Place Saint Marys,Portsea,Hampshire,England

ENGLAND MARRIAGES, 1538–1973
Indexing Project (Batch) Number M06261-2
System Origin England-ODM
GS Film number 919744, 919745, 919746, 919747

Try searching this site its free. its where I found most of the above:

familysearch.org/search

I am related to Jemima Oxenham and Richard Burgess Sayer I have been able to track Jemima Sister Sarah Oxenham whom was George Batten immigrated to live near Melbourne Australia and also Sarah married second husband Patrick Stanley contact email:- rossleonard.rs.sayer6@gmail.com