...He was feeding someone.
I couldn't get very close, so I put the camera over the nest and shot this photo. It's hard to see how many babies there are, but as far as I can tell, there are maybe four.
***Note to my loyal readers: I very nearly bled to death getting this shot for you. The nest was in the middle of multiflora rose, honeysuckle and a downy hawthorn. Know why it's called "hawthorn"? Yep, full of thorns. I trimmed back as few branches as possible so as not to blow the cardinal's cover. See the level of dedication I have for you?