Swallows in the Shop

Hello everyone.
Swallows are beautiful birds. Each summer they come back. They start making nets in my fathers shop more than 10 years ago and each year they come back. First one of parents comes and look around and they start building nest. When ready they lay eggs and after some time younglings come. Sometimes there is three small birds and sometimes it is four ( last couple time I think it was four ) (edit - found photo of five swallows in the nest, on the end of the post,so it can be five small ones as well) . When they are this big they just wait for food and parents keep bringing food in all day - until sun is there food keeps coming. There is small opening on the window just for them so that they can leave with early sun and bring food. In the begging they struggle a bit but later they learn how to enter really fast through opening. They can fly steady or lets say "to hover" in air so it is easier for them to enter through openings. And this ability is handy when they catch insects. They easily pick up flies in shop.
Younglings wait in nest and when one of parents in back they start asking chirping and asking for food.
When they grew bigger and start to spread and stretch their wings then parents do not bring food in nest. Instead they try to lure them out of nest by standing somewhere close but not that much close of the nest.
Then one by one younglings fly over to next spot and they start flying around.
When they learn to fly they explore and at night they come back together to sleep over in shop. These are very joyful times since they fly together and try to catch each other all over the shop. You can see three or four younglings that are flying around shop and making cheerful sounds like they are kids that play with each other. At night they stay on upper parts of shop - electric wirings on the wall.
Sometimes you can hear very strong and different sound parents make. It is most likely sound for danger and most probably there is cat near or inside the shop. Or when some stranger enters shop they tend to make noise and fly low around that someone. But they get used on my father and sometimes they rest around when he is working.
After some time swallows lay eggs again and nest again.
So there are usually two nest of younglings through year in the shop - as I remember.

Here they wait for food. They look down at me. Funny how they look like Penguins of Madagascar when they look down. There was video of one of parents arriving with food so when I find it I will try to post it. Joy and chirps from younglings.