Hi thanks for the reply,
I can find them in every census from 1871 to 1911.
I've tried but I just cant find them in 1841,51 or 61.
I know that william bevan, who was my gggrandfather, got married in 1864 to margaret griffiths, and that is them on the 1891 census.
William bevans father was also called william bevan.
Ive found a possibility on the 1851 census, a william bevan with a son called william bevan,born about 1839 living in Rassa Houses and married to ann bevan.That could be them.
Could you look on the 1841,1851 or 1861 censuses for them?
Maybe somebody else would be able to spot them.
Maybe i will have to wait for the parish records on findmypast or buy some certificates to find out more.