The "Weekly" Biology Session: New life

As I have mentioned on Facebook, we have some flying visitors! We have two bird houses, one on the wall of our house in the front yard, and one in the back yard on the wall of our shed (depot?).
Last Sunday, as I was doing private business on the toilet (yes, I know, very informative) I heard peeping and flappering on the wall of the toilet. And when I looked out the window in the kitchen I saw a great tit (koolmees or parus major) sitting on the bird house, and entering it. We have a chicks!
I got these bird houses for my birthday and Big Man and Little Man installed both bird houses last summer, but we realised it was near the end of the breeding season of both the little tit and the great tit. The bird house in the back yard was used during the winter for overnight stays (Big Man found feathers and poops when he was cleaning it over two months ago), so we knew some birds knew of the existence of the bird house.
So when Big Man was putting Little Man and Little Lady into their Sunday bath, I picked up the camera, put on it my telelens, and grabbed a chair to see if I could get some pictures of these lovely little birds. We have lots of birds visiting our garden, but great tits make up the greater part of it.

This is the view I got as I was nearing the front yard! Busy, busy birds. Mom and dad busy with feeding their chicks and on the watch out.

On and off they went.  I sat there probably for 10 minutes and they made three trips in that time.

I do not know why this tit is picking and hammering at the opening of the birdhouse. He or  she did it every time while hanging there.

Clear shot of probably a female great tit.

There is also news on the bird house in the back yard. The last couple of days another couple  of great tits is inspecting the bird house. Flying on and off, going in and out, calling to eachother from the roof of our shed and the fence between us and the neighbour. You can hear them clearly, they are very busy! Exciting! Two nests! As I am typing, both tits are in the bird house in our back yard! Hopefully all the chicks will grow up and will not be catched by either our cat or the neighbourhood cat. Will keep you posted.