The Watkins side of the family appears to originate from near Talgarth/Brecon, with Levi Watkins senior being born there 1838. Likely 1841 census entry (spelt Leavy) at Cuminbach, Llandefalle (written as parish of Llandefalley South), in Breconshire. Remarkably near the base of my good friends at Bicycle Beano! The photo below (was the banner photo for the website) was taken at Llandefalle church – plenty of Watkins names on gravestones here.
NORTH AND SOUTH LLANDEFALLEY – Extract from National Gazetteer, 1868
“NORTH AND SOUTH LLANDEFALLEY, a parish in the hundred of Talgarth, county Brecon, 5 miles N.E. of Brecknock, its post town, and 6 S.W. of Glasbury. The parish forms two divisions, known as North and South Llandefalley. The village, which is considerable, is situated a little to the S.W. of the river Wye. In the vicinity is a medicinal spring impregnated with sulphur. The living is a vicarage annexed to that of Crickadarn, in the diocese of St. David’s. The church, dedicated to St. Matthew, is a spacious structure with stained-glass windows and a timbered roof. It contains monumental effigies of two prelates. The charities produce about £8 per annum. There are traces of an ancient camp. Trebarried and Trebris are the names of former seats, now in ruins.”
Transcribed by Colin Hinson 2003, http://www.genuki.org.uk/big/wal/BRE/Llandyfalle/Gaz1868.html
The 1851 census hasn’t yet been spotted, but he married Phoebe Griffiths in Merthyr Tydfil 13 June 1859 and was then living at New Tredegar.
Other Watkins family trees online have origins clustering around Radnorshire and the Marches (Welsh border country into Herefordshire). Many no doubt inter-relate in the mists of time.