I have a young cockerel that is brownish and reddish and parts are gray, but it's all barred. His father is a Barred Plymouth Rock and the mother is a mutt where she has a maroon chest and white on the rest of her body. Other chicks are the dark gray and Barred. But why is this cockerel brown and barred? Sorry it wouldn't let me post a picture.
It's very common for Barred Rock mix chicks to be colorful. Usually, it's the males that get the most color. This thread has some good pictures of what can result from crossing Barred Rock roosters. https://www.backyardchickens.com/t/413047/crossing-buff-orpingtons-with-barred-rocks
