09:46 am: One of the Tree Sparrows was inside the nest, the other flew to the entrance hole chirped and then flew to the tree. After some seconds, the Sparrow inside the nest left the nesting box. The second Sparrow flew to the nesting box and waited at the nesting box entrance hole with a big fat worm in its beak. It chirped a couple of times, looked around, chirped again and then flew in. So....? Was the male wanting to feed the female? Or was it the other way around? Or was it the male taking with himself a big fat worm to feed on whilst on duty in the nest, or was it the female? Or was it one of the parents just wanting to feed hatchlings? I do not think it is the latter, due to the fact that once in the nest the bird settled really quickly, no sound was/is to be heard and the feeding frequency seems to be too low, but perhaps I just missed a few.
09:52 am: The bird leaves the nest (flew into the tree) with no duty-replacement-bird and with nothing in its beak. (Outside temp: ca. 24°C in the sun already, ca. 14°C in the box)
10:00 am: A Sparrow enters the nest with soft nesting material in its beak, fixes a bit and settles in the nest (@ 10:06 still in nest). So no hatchlings.