Yellow-crowned Night Heron (?)

Description:

I'm 99% sure that these are two immature YCNH sunning themselves in the top branches of the live oaks where an active YCNH colony is located. I know it takes about 3 years for these herons to put out adult plumage (it looks like the immature heron on the right has a downy hint of a crest starting.) The bare spot on the heron to the left that has me completely puzzled. Do immature birds develop brood patches?

Habitat:

Yellow-crowned Night-Herons live in or near wetlands—on the coast along islands, mangroves, and barrier beaches; farther inland in wooded swamps, forested uplands, and lakes and rivers, sometimes near residential areas. They usually nest in small colonies, sometimes with other wading birds, and forage along tidal marshes, in tide pools and the shores of water bodies where crustaceans are abundant

Notes:

Spotted in White Point Garden, Charleston SC