Booked family (BA AVIOS) flights 2 hrs ago (to europe) - just realised I have booked my 12 year old 'boy' as a child (booking process does not ask for DOB's to sanity check my mistake) and went through no issue

just realised accordingto BA he is not a child ; I should have booked him as a "man" (adult)

What do I do - anything ?

Cant afford do lose the avios flight back in to the system and potentailly lose them, lose them

p.s. just booking the return via Ryanair (sorry) and he is a 'child' until he is 16 ! - is there not a global age definition for flight ?!?

Thx
Q5