Not the greatest of all photo's but I almost caught this male feeding his babyluv! He keep flying away while she sat in the feeder full of food and come back in a few minutes and feed her whatever was in his mouth. It was great fun to watch. I think he loves her! Can you say "twitterpated"?
Cardinals love sun flower seeds!
They also like a bit of undergrowth in your yard as they like to forage near the ground. I Put seed on the ground as well as in the feeders and often see the Cards down with the doves eating.