Hello Ann,
Welcome back to your thread

Thanks for clarifying why you think John Henry's birth was circa 1866/7.
I'm not convinced he was born so early. If Hannah 1901/11 staying with the Cocking's, is John's mother, then I believe the 1891 census posted on your thread is 'your' John, and he was born circa 1873. Also the 1901/1911 census have recorded his age as circa 1873.
So, the question is: are the census records mentioned above another John? If not, why would he consistently state his birth year circa 1873, if infact he was born 1866. If he was born 1866, and James and Hannah married 1871, surely his birth should be registered as John Henry Sykes as Sykes was his mother's name.
Do you have any other bits of info you can share with us, anything which may help the search?