I had a look on Family Search and on the 1911 census I am only seeing one John R born in 1878. Parents are Robert and Ann and father and son are slate splitters. His birthplace is Llanllyfni Cvon and residence same.
There is a Winifred Jones as boarder and Rowland Pritchard as visitor.
Jamjar
Added:
The family with daughter Jane A living Eivion Terrace, Llanllyfni, Caernarvonshire, Wales
On the 1891
Page Number: 65
Registration Number: RG12
Piece/Folio: 4655/ 118
On the 1901
Schedule Type: 126
Page Number: 18
On the 1881 at Coetmor Terr
Page Number: 40
Registration Number: RG11
Piece/Folio: 5562/124
Can only see one birth for John:
PARRY, JOHN mmn JONES
GRO Reference: 1878 J Quarter in CARNARVON Volume 11B Page 530