Have you looked on National Archives site?
Shows will of John Weatherstone a framer, 1847possible grandfather of your John, and a PARDON for a John Weatherstone in 1835 Nat archives ref CRIM1/582/2 IN 1835, which would be before he married. A Richard Weatherstone was acquitted of something in 1820 (possible brother? as one of John and Catherine's children named Richard.
Parents of John could be Anthony and Elizabeth of Windrush, 1810 or Edward and Margaret also of Windrush glos.