Hi there, posting here for traffic!
A Jay flew into the garden with three baby birds in its beak about an hour ago, it dropped two of them which were dead, but the third is sheltering in a bush. Usually I'd obviously leave a fledgling well alone but this one seems quite small still (although partially feathered and hopping) and I doubt its mum knows where it is, given the Jay seemed to fly in from a different garden. The Jay is now also still trying to get at it, is there anything we can do? 
Thanks!