Kath, on the 1851 census it shows Sarah's father William as having been born in Liverpool, but on 1841 it says Warwickshire? but that is on the transcription and not shown on the census image so may be an assumption on someone's behalf. I've done a bit more looking and your William has actually a third place of birth! On the 1881 census he is with his wife Ann and Grand-daughter Sarah Ann Grolage (probably should be Groutage), he is still listed as a Japanner but this time is place of birth is Plymouth, Devon.