Thank you all so much for your replies. I didn't think I had the right parents so now I can delve further backwards.

Knew I could rely on Sheffield Indexers.

Jenny

Did John Snr remarry? I have found a burial for a John Turton on 24 Jan 1889 (aged 72) living at 23 Regeant Terrace, he was buried at Ecclesall All saints. Could this be your John?

Turton seems a very popular surname.

That's something else to look into. Thanks for your help.