Try making the contact print with the negs out of the Print File sleeve first. It may be uniformity issues with the plastic.
Are you talking about the lighter blotches above the child's head in the only full frame? If so they look like they are lighter than the rest, meaning plus density. With air bubbles you get slightly darker patterns, because the air bubbles actually prevents development in the area it touches the film. When you see something of lighter tone in a print, it would be developed MORE, which doesn't make sense.