No wonder I couldn't find Elizabeth after 1841. And her baptism doesn't seem to be in the IGI.
The only thing I'd discovered about her was that she had an illegitimate son, John Kewley Sayle, bap 3rd Dec 1854 in Bride, who appears in the 1861 census as "John Kewley" living with grandparents John Sayle and Ann nee Cowle. I haven't followed up what became of him.
I'd be interested in learning more about Elizabeth and Henry Sidebotham's family. Using the information in your message, I found Eliza and John Corkan in 1861 in Salford with baby Elizabeth b Bride, staying with John Corkan's uncle Thomas. And I found Elizabeth and Henry Sidebotham in Chorlton on Medlock in 1871 with baby Alice A, but no sign of Elizabeth Corkan who would have been 10.
I think that Ralph Sayle will probably be very interested in this, too.
Jean C