Our female kestrel had a successful hatching of 4 kestrels about 5 days ago and today she laid another egg. I assume it is the same female. Is that typical? We have a nest box camera and can watch the nest at any time. And have not seen any disturbance or other birds in the nest. It seems to be a white egg about the same size as the others she laid. Last year we also had a successful hatch of 5 and there was no additional egg laid. Has anyone else had this happen?