Eve,
No I am not further back to before C1851.
"Did Ruth marry her step-brother ? "
I am going to be careful in answering this, mainly because I am not sure of the legal status of "step-brother or step-sister" ??
But Step 1 ...her widowed mother ( Alice Spensley nee Batson) married widower George Yeoman (who had a son James) in 1875.
Step 2...On Census 1881 George, Alice Yeoman and 21 yr old James Yeoman etc are in one "household" at 35 Maple Street, Bishopwearmouth, Sunderland (4987-42-77)
At the same address is another "household" consisting of four of Alice's Spensley children, including 18 yr old Ruth Spensley.
Step 3....In 1889 James Yeoman marries Ruth Spensley.
So yes, Ruth married the son of her mother's second husband... and James married the daughter of his father's second wife !
Ouch.
Michael Dixon