It just looked to me like the Chaffinch was acting referee between the two House Sparrows. Thought it appears to be a young one begging - not sure Dad is that interested though.
Another shot of a white-tailed Chaffinch, which the IDer's say is not leucism but normal summer moult. Never seen it before though.
TTTW
Shutter Priority settings
f/5.6
1/800 sec
ISO 800
Exp bias -0.3
Focal length 103mm
Max aperture 3