There is a marriage for John Jones in Caerhun on 27 January 1849. The details are:
John Jones, full age, labourer, bachelor, abode Roe, father Robert Jones, labourer.
Ann Thomas, full age, spinster, abode Roe, father Hugh Thomas, labourer.
Witnesses were@ David Jones and David Parry. Bride and groom made their mark.
The family I found in the 1861 census in Llangelynin, included Robert Jones, Lodger, widower (?) age 83, formerly ag lab, born Dwygyfylchi.
It appears that this Robert Jones was the father of John Jones b 1825.
In the 1871 census John and Anne Jones are living at the same address in Llangelynin. This time Anne is shown as being born in Gyffin.
In the 1881 census John and Anne Jones are living in Pant yr Afon in Caerhun. Anne is shown as born Gyffin there too.
1891 census has them in Rowen, living in Ty Hen and once again, Anne is shown as born Gyffin. They remain there in the 1901 census.
There are Family Trees for them on Ancestry. One of them has John Jones death in 9 July 1905 in Ty Hen, Rowen. Both John and Ann Jones were buried in Llangelynin cemetery.
Robert Jones b1779 was buried in Caerhun on 10 February 1863, age 83 and his abode was Ffridd Y Ddwyffrwd.
I don't know which direction to head in next. Would someone like to suggest something?