Hi Hifly,
This MIGHT be the family in the 1861 census (prior to the birth of the two boys you are looking for). Right place - right time; and the only clue that I can find in Glamorgan!
RG9/4066, F40, Page 27, Sch 111.
All surnames VALLIS but transcribed as VALLES; Canon Street, Aberdare.
John, Head, Mar, 33, Chandler, Somerset
Louisa, Wife, 35, Somerset
Oops - pressed "Post" by mistake!
Eliza, Dau, Un, 14, Somerset
Ellen, Dau, Un, 12, Somerset
Mary Ann, Dau, 10, Aberdare
William, Son, 3, Aberdare
John, Son, 1, Aberdare
2x Boarders - I'll post details if required.
Regards,
Lee.