Hi,
I do not have access to Llanfaes parish records but I may have found the birth you are searching for – although the mother's maiden name is Jane Owen:-
Richard Roberts, father Richard, mother Jane Owen, b. 25 July 1850, Llanfaes.
If this is the correct birth the following, all born at Llanfaes to parents Richard Roberts/Jane Owen, may be siblings.
Anne – 13 Sep 1867
Edward – 6 Nov 1869
Evan – 20 July 1855
Griffith – 18 Jun 1871
Humphrey – 11 Jan 1862
Mary – 16 Dec 1865
William – 18 Aug 1857
(there is also Jane – 25 Apr 1852 – but the birth was registered as taking place in Beaumaris).
You will find these birth registrations on North Wales BMD if you search with mother's maiden name Owen.
I expect you have seen the 1851 census (HO107/Piece2517/Folio232/Page 42) which seems to be the family living at Llanfaes. In order to clarify Jane's maiden surname I have searched for Anglesey marriages between Richard Roberts and Jane (Owen/Williams) in the years before 1851 and found one likely record:-
Richard Roberts, bachelor, labourer of Beaumaris, son of Humphrey Roberts, labourer married Jane Owen, spinster of Llanfaes, dau of Richard Thomas, smith on 18 Jun 1850 at Llanfaes Church.
(Which raises the question why Jane daughter of Richard Thomas is referred to as Jane Owen in the marriage registration and the birth registrations of her children?)
Richard Thomas, blacksmith at Llanfaes and daughter Jane aged 8 can be seen in the 1841 census – HO107/Piece 1363/Book 6/Folio 5/ Page 4.
Perhaps you have other information which will confirm some of this?
