I'm pretty sure. Of course, I've been known to see what I want to see.
But what I saw when I first started watching was three greedy beaks craning for food and slowly the little heap behind the others (but closest to the camera) struggles up with his little head just a wavering and his beak a-gaping as best he could. I'm sure I saw four beaks at that point.
When it seemed (IMHO) the newest chick wasn't getting his fair share, I ended up concentrating on willing food to be dropped into his beak. He didn't have the best aim. The others seemed quite adept at getting their beaks where mom's was going! Princess was doing a great job of doling out though!