For the last 2. 1/2 days a robin has been hanging around my back deck. He has been flying up and down on my back door as if he is trying to get in. He is popping all over the back deck, and furniture. When I open the door he flys away, but eventually comes back. I am concerned that he is sick. Is there anything I should do?

Robins become very territorial this time of year as they start nesting. I'm guessing that you have a male robin who is seeing his reflection in the glass doors. He has to get rid of this "intruder". Which is why he keeps flying at the door. As long as he can see his reflection, he'll keep up this behavior. (They are pretty, but not that smart). Temporarily hanging a curtain or piece of plastic on the outside of the door will keep the bird from seeing its reflection.