Strange. The young great tits in box 3 died a day after the female left. We thought it was the male returning. However, a bird started to bring in new nesting material. Initially, we thought that it had unearthed some unhatched eggs but there are now 4 eggs in the nest, probably new ones. Is it the same female? Difficult to tell, but it seems unlikely.

2nd Laying in Box 3 (Great Tit)