Congratulations Sherwood - you've found GGG-grandparents and GGGG-grandparents! A few tidbits you may have discovered already, but, just in case:
1. Abel Pentney married Marry Thurston in No. Elmham. Two dates are given in IGI: 7 Apr 1797 and 22 Apr 1797
2. John Pentney married Rosetta Barwick in No. Elmham, 29 Jun 1837 (BMD).
3. John possibly died Q1 1877, Walsingham
4. Looks as if, in 1881, James J. Pentney was married to Lydia, b. abt 1841, Kent. Their children were Eliza (age 11), George (age

and William (age 10mo.) Eliza and Geo. were born in Peterboro, Northamton, and William in Carlton, Nottingham, where the census took place. (James was born in Lynn Nfk)
5. Children of Abel and Mary:
- Mary, ch 27 Oct 1801, No. Elmham
Lydia, b. abt 1803, No. Elmham
Peter, ch 28 Sep 1807, No. Elmham
Frances (f), ch 1 Nov 1809, No. Elmham
Philip, ch 26 Mar 1813, No. Elmham
William, ch 11 Jul 1816, No. Elmham
James, ch 25 May 1818, No. Elmham
(From IGI, and Norfolk Transcription Archive)
Too bad there's not more on Jarys.....

Regards, Nor_Fam