Now we have 5 fledged and 2 left in box in good health

I did not see all the nestlings last time, but there were several. One was puffed up and covered the ones asleep.

Two have fledged and two are left. They should leave by the end of the week. You can see the blue on the feathers. The tail gets a little longer and flight feathers grow a bit more.

Swallow nestlings are very similar until the bill gets longer, when birds are about a week old. But they never get the blue, they are gray in the box. Tree swallows as adults can have a bluish tint, but not when in the box.