While hiking, I heard an interesting call so I looked up and saw a Northern Flicker hovering midway up a large tree. When the bird moved away, I saw that there was a juvenile in the tree cavity, and it was the one who was calling. It appears that the juvenile is a male Northern Flicker and I also got a photo of his father perched in a nearby tree. After taking these photos I quickly moved on so as not to disturb them further.

I am assuming these are two forms of the same species, as they seemed to be interacting positively with each other, but will separate if that's not the case.

UPDATE: split observation. For the bird on the right, see here.