So, after a few quiet days, my daughter and I decided to open up the birdhouse and remove the nest, cleaning it out for the next year. We slid it out, and placed it in a box (which is now on a shelf in the shed...can't throw it out, but don't know what to do with it!). Here is a pic of the nest still in the birdhouse:
Once we had the nest in the box, we searched a bit to find any evidence of eggs. We only found one little egg, with a TINY hole it in. The only other egg we'd found was found on the ground a month or so ago. So, I'm now assuming that the little bird we saw peeping out of the whole for three or four days straight was the baby fledgling.
On a whim, we decided to check out the other birdhouse in the yard. When the birds first came back to the yard, we saw them making a nest in the other house. However, this house never seemed to have much activity. They focused on the one above.
When we opened the house up, we were very surprised to find a full nest and THREE EGGS!! We quickly took a picture and put the nest back in the house. Some internet searches have confirmed that putting back a disturbed nest is the best thing to do. I also learned that birds really don't abandon their babies/nests when humans have touched them. So, here's a picture of the nest. I don't see any birds going in/out of it, so I'm really not sure what will happen to these eggs. Will they just sit there?? We'll check it again at the end of the summer.