A few days after cleaning off the mud nest, I looked out my front window after dusk.  There on the ledge where the nest had been were the two birds roosting!!.  They hadn't started to rebuild the nest, but they were sleeping there.  Odd!  Doug taped some deer block netting up there to keep them from roosting in front of the door.  Then only one bird was roosing on the next ledge, but at least not in front of the door.  That went on for a long time, with me wondering where the other bird was.  Did they have another nest, and the mother bird was sitting on the eggs?  Was the other bird killed?  I felt sad that this single, solitary bird was sleeping there alone.  However, this week, Thursday night, we looked at and BOTH birds were roosting there again.  Good grief--a messed up porch again!  Does anyone know why they would do this?