Hi, 
I think you will need to buy a copy of the birth certificate.
FreeBMD has this registration but too many differences:
Aubrey J Chapman   DecQ 1920    Salisbury    5a    295      (mother Burt)
Possible marriage registration:
Wilfred G Chapman    SepQ 1915    Salisbury   5a    479
Bride:  Ethel M Burt
Can't see an Aubrey Walker Chapman.   

     Just found a birth for an Aubrey W Chapman  DecQ 1912 in Warwickshire.   

Nanny Jan