Hi again can confirm that Elizabeth was not with Owen & Catherine in 1851 Bryn Y Fforch, having problems with Elizabeth you have from 1861, what year of birth/place of birth does she give?
Keyboard86
EDIT i have located a marriage 1st December 1852 Liverpool St David of a Thomas Davies to an Elizabeth Rowlands he was a Mariner, the father of Elizabeth is Owen Rowlands but the occupation is not that of Copper Miner /Miner or similar, could even possibly be a Steward?