Cardinals mate with the same partner each breeding season. They will breed two or three times during the summer. The female builds a nest in dense shrubs or thick bushes. She will lay three to four eggs and incubate them; remaining in the nest for 11 to 13 days. During this period the male cardinal will feed the female. Both male and female cardinals care for and feed their young. In the first few weeks the chicks are fed only insects. Young cardinals begin learning to fly around ten days after hatching. The parents continue to help feed their chicks for several weeks after they have left the nest. The chicks will usually flock with other juveniles until they are mature enough to establish their own territory. Cardinals have a lifespan of 15 years in the wild.
Info from Northern Cardinal Facts: https://forum.americanexpedition.us/northern-cardinal-facts