Bluetit nest - a problem? (1 Viewer)

Hi - I have a web cam nest box. A bluetit has been roosting in it all winter. It spent about two weeks building a nest. Although two were about it seemed maybe only one was building the nest. Yesterday there was an egg in the nest but the female seemed out and about with no sign of incubation. However it returned overnight. There is now a second egg but the female does not appear to be sitting on it. Is the behaviour of a female abandoned by the male or normal, or something else? I'm not sure what should be happening.
Thanks,
Dave

I should add there does not appear to have been any external interference or disturbance.

She will start incubating when she has finished laying the clutch.

Chris.