What I have in my tree...
Henry Williams, baptised at Llantwit Fardre on 18 Feb 1811, son of Richard Williams and Jane Evans (married on 30 Jan 1806 at Llantwit Fardre).
He married Gwenllian James on 21 Dec 1835 at Eglwysilan, and they had at least 11 children, Ann, John, Henry, Mary, Sarah, Edmund, Gwenllian, Richard, William, Jane and Thomas from 1836 to 1860.
He was a boatman until the 1871 census when he was a labourer, living close to the Glamorgan canal in Gabalfa in Cardiff.
Gwenllian died in 1876; Henry in 1880, buried at Eglwysilan on 2 April 1880.
I'll PM you the name of the Facebook group and it's creator.
Edited to add: none of this is proven with certificates, only parish records and census data. And no fathers named in 1835 to guarantee Henry is the same Henry as the baptism son of Richard.