Hi PeterLS, welcome to Rootschat

I'm rather puzzled by this one - looking at Wilfred LAWSON and his wife Caroline in the 1851 census, they were aged 55 and 57 then and their youngest child was aged 12. No Ruth

There were a few Ruth LAWSONs born in Cumb in the 1840s
One (in Maryport) had a father Thomas who was a labourer.
Another had a father Robert (b 1808) who was a solicitor.
Yet another had a father Robert who was a Builder.
Finally, one was stepdaughter of a Cowkeeper.
I can find a possible marriage in
1867 of a Ruth LAWSON to a John Henry ERSKINE, they were in Co Durham in 1871. John Henry was an Engine Driver at an Ironworks, not a knight of the realm.
Ruth was apparently married to a George SMITH in 1881, he was born about 1844 in Stourbridge. John Henry ERSKINE had died in 1872 and she married George SMITH in 1873. This appears to be the only Ruth ERSKINE marriage in the 1870s.
Finally, in 1891, Ruth gives her birthplace - Maryport - suggesting that she was Tom the Labourer's daughter.
I realise that none of this is in agreement with what you said. Please don't dismiss it out of hand. Of course, if you have nothing to do with the SMITHs, I am on the wrong track.