I had earlier posted a picture of our nest box from last Saturday with some tiny great tit chicks.
A week later they have grown a lot and look absolutely piled up in the nest! It's hard to know how many chicks are there...but clearly the feet are well developed, wings beginning to form and head, wing and leg feathers are in evidence.
thehomelyyear
Pro 
That's an amazing photo. It's really hard to tell one chick from another...wonder how many there are.
Margaret and Noreen