During the last few days I have seen very unusual feeding with a blue-tit and a sparrow, they sit side by side on the branch of my tree and then the blue-tit drops down for mouthful of food, takes it back to where the sparrow is and the puts it under her/his foot and they both eat it! then the blue-tit gets some more etc, I wondered if perhaps a sparrow had laid an egg in the blue-birds nest? Anyone else seen this type of behaviour in birds? Blue tits nest across the road from us and the sparrows nest in our hedges.