Thank you ThrelfallYorky,
I think from later census, Emma Johnson was born around 1824, but it gives place of birth as Liverpool.
On her marriage certificate in 1847 at St Philips Church, Liverpool, the witnesses were John and Elizabeth Hewitt. I had a hint that Elizabeth could have been Emma's married sister. I did find a record of marriage in 1834 - Elizabeth Johnson to John Hewitt but no father's name given.
Any help is welcome - I am really struggling.
Loz57