I see that Edward spent his adult life in Llangollen and was down as a brewer in the 1881
This just might be the marriage of Thomas, Senior, in Llanarmon:
8 January 1813 Thomas Roberts and Ann Jones both of the parish, by Banns. witnessses David Hughes and Thomas Lewis
It's not for certain though and need to check up the marriage of Thomas jnr.
In 1841 Thomas, snr, is here:
Nat y glog, Llanarmon DC
HO107/1399/7/5/2
Roberts
Thomas, 50, butcher
Ann, 55
Edward 26, Ag lab
David, 14
Mariah, 9
All b. County
and it looks like Thomas Roberts, jnr, is already away from his parents, working as a Male Servant
Pen y Bryn, Llanarmon DC
HO107/1399/7/6/3
Thomas Roberts, 20, MS, b. County
Gadget