Juvenile Pileated with Mom

We've always had pileateds around and knew they nested if not on the property, nearby, but this year is the first time I've had the chance to watch the female feed a juvenile at our feeders.

Once he figured out which feeder had the good stuff, the young male moved to it and spent a good 20 minutes on it. While watching  him, I noticed he has white wing tips. Not sure how common that is. Any input?

Here's a video of them at the feeder. Very quietly in the background you can hear him making his odd, wheezy, grunting sounds. The first time I heard them I thought it was an upset squirrel. Turns out they're the begging sounds he makes when he's around Mom.