While watching robin baby #2 who's hunkered down in the bushes (well hidden) I heard the click call of Papa-to-be Cardinal. He was above my head on a branch. Out of the bushes flew Mama-to-be Cardinal. I know there's a nest close to the hunkering baby robin. Mr. Cardinal had a mouth full of worms. He fed his mate. There is nothing more loving and tender. After her meal she groomed her feathers and within five minutes she was back hidden in her nest. She's obviously an experienced mother, knows to take very short breaks. Obviously the cardinals and robins co-exist in peace, because Papa Robin flies into same bushes to feed baby #2 without being attacked by the cardinal and the robins' (now vacated) nest is right across the path from the cardinal nest. There were no territorial problems.
Baby robin pictures tomorrow. All is fine.