Hi, Some Robbins built a best above my front door. I left them alone while they built it and marveled at their work. Friends said that I should not, because once the babies hatch the parents will be dive bombing and attacking me in defense. This hasn't happened. Two chicks were born and hatched several weeks ago. Parents would come and go. When I came in and out alone or with my dog. Sometimes flying off or running on the ground to lead us away from the nest. Sometimes standing a short distance away with bugs in their mouth for the chicks waiting until I passed by. Chicks heads could be seen sticking above the nest at times. My new neighbors and I have been coexisting quite peacefully. A week ago, I found one of the chicks on the cement dead. No where near developed enough for its first flight. Nature can be sad. I know sometimes chicks can fall out or be pushed out of nests. I don't know why. Second baby was still there. Three days ago, work men were working on the concrete sidewalk out side of my apartment. I saw one parent Robbin perched on the overhang gutter just above looking down at me. It didn't fly off. Just sitting there. I have not seen parents or the chicks head since then. I been tempted to peek into the nest but have not. Will Robbins abandon a nest with a live chick? If so why? I'm wondering if the work men did anything to the nest. If so, I'll be mad. I miss my avian neighbors. Live and let live
I understand your concern, and yes, it's very hard to watch nature take it's course some times. I have not heard of a parent willingly abandon it's nest if there's live chicks in it. A disturbance nearby might scare it off for a few hours. Are you able to stand on a ladder to quickly peek in the nest? Or another solution is to attach a hand mirror to a long pole (at an angle) and you can use it to peek over the top/side of the nest. It sounds like it might have been too soon for the remaining chick to fledge (old enough to leave the nest), but I guess it's another possibility? I hope this story has a happy ending!
PS Robins are not usually dive-bombers :)