Hi Sunriseuk
Thats the risk we occasionally have to take to find our rellies
..and even if it is the wrong one its not money totally wasted as you then know not to follow that line.
You could order the cert and specify that you only want it if father is James and if it isnt you only have to pay £3.50 for the search.
The Philip Willis birth I found is the only one in the time frame b Aston-Warwickshire and Aston is the Reg District for Birmingham.
You know from his marriage cert he was b abt 1900 and that his father was James so I think its a very strong possible he is your guy.
Did Philip have any siblings you know of ?
There may be further info on the 1911 cencus but you need to buy credits to access the details
Good Luck
Jane